Bank deposits – turning unsecured loans to highly leveraged companies into (mostly) risk free assets – an Australian perspective

The ability to raise funding via “deposits” is one of the things that makes banks different from other types of companies. As a rule bank deposits benefit from a variety of protections that transform what is effectively an unsecured loan to a highly leveraged company into an (arguably) risk free asset.

This rule is not universal however. The NZ banking system, for example, has a distinctly different approach to bank deposits that not only eschew the protections Australian depositors take for granted but also has the power, via its Open Banking Resolution regime, to write down the value of bank deposits if required to ensure the solvency and viability of a bank. But some form of protection is common.

I previously had a go at the question of “why” bank deposits should be protected here.

This post focuses on the mechanics of “how” AUD denominated deposits held with APRA authorised deposit-taking institutions incorporated in Australia (“Australian ADIs” or “Australian banks”) are protected. In particular, I attempt to rank the relative importance of the various protections built into the Australian system. You may not necessarily agree with my ranking and that is OK – I would welcome feedback on what I may be missing.

Multiple layers of protection

Australian bank deposits benefit from multiple layers of protection:

  1. The risk taking activities of the banks are subject to a high level of supervision and regulation (that is true to varying degrees for most banking systems but Australian standards do seem to be at the more conservative end of the spectrum where Basel Committee standards offer a choice),
  2. The target level of Common Equity Tier 1 (CET1) capital required to support that risk must meet the standard of being “Unquestionably Strong”,
  3. This core capital requirement is supported by a series of supplementary layers of loss absorbing capital that can be converted into equity if the viability of the bank as a going concern comes into doubt,
  4. The deposits themselves have a priority super senior claim on the Australian assets of the bank should it fail, and
  5. The timely repayments of AUD deposits up to $250,000 per person per bank is guaranteed by the Australian Government.

Deposit preference rules …

The government guarantee might seem like the obvious candidate for the layer of protection that counts for the most, but I am not so sure. All the layers of protection obviously contribute but my vote goes to deposit preference. The capacity to bail-in the supplementary capital gets an honourable mention. These seem to me to be the two elements that ultimately underwrite the safety of the majority of bank deposits (by value) in Australia.

The other elements are also important but …

Intensive supervision clearly helps ensure that banks are well managed and not taking excessive risks but experience demonstrates that it does not guarantee that banks will not make mistakes. The Unquestionably Strong benchmark for CET1 capital developed in response to one of the recommendations of the 2014 Financial System Inquiry also helps but again does not guarantee that banks will not find some new (or not so new) way to blow themselves up.

At face value, the government guarantee seems like it would be all you need to know about the safety of bank deposits (provided you are not dealing with the high quality problem of having more than AUD250,000 in you bank account). When you look at the detail though, the role the government guarantee plays in underwriting the safety of bank deposits seems pretty limited, especially if you hold you deposit account with one of the larger ADIs. The first point to note is that the guarantee will only come into play if a series of conditions are met including that APRA consider that the ADI is insolvent and that the Treasurer determines that it is necessary.

In practice, recourse to the guarantee might be required for a small ADI heavily reliant on deposit funding but I suspect that this chain of events is extremely unlikely to play out for one of the bigger banks. That is partly because the risk of insolvency has been substantially reduced by higher CET1 requirements (for the larger ADI in particular) but also because the government now has a range of tools that allow it to bail-in rather than bail-out certain bank creditors that rank below depositors in the loss hierarchy. There are no great choices when dealing with troubled banks but my guess is that the authorities will choose bail-in over liquidation any time they are dealing with one of the larger ADIs.

If deposit preference rules, why doesn’t everyone do it?

Banking systems often seem to evolve in response to specific issues of the day rather than being the result of some grand design. So far as I can tell, it seems that the countries that have chosen not to pursue deposit preference have done so on the grounds that making deposits too safe dilutes market discipline and in the worst case invites moral hazard. That is very clearly the case in the choices that New Zealand has made (see above) and the resources they devote to the disclosure of information regarding the relative risk and strength of their banks.

I understand the theory being applied here and completely agree that market discipline should be encouraged while moral hazard is something to be avoided at all costs. That said, it does not seem reasonable to me to expect that the average bank deposit account holder is capable of making the risk assessments the theory requires, nor the capacity to bear the consequences of getting it wrong.

Bank deposits also function as one of the primary forms of money in most developed economies but need to be insulated from risk if they are to perform this role. Deposit preference not only helps to insulate this component of our money supply from risk, it also tends to transfer the risk to investors (debt and equity) who do have the skills and the capacity to assess and absorb it, thereby encouraging market discipline.

The point I am making here is very similar to the arguments that Grant Turner listed in favour of deposit protection in a paper published in the RBA Bulletin.

There are a number of reasons why authorities may seek to provide greater protection to depositors than to other creditors of banks. First, deposits are a critical part of the financial system because they facilitate economic transactions in a way that wholesale debt does not. Second, they are a primary form of saving for many individuals, losses on which may result in significant adversity for depositors who are unable to protect against this risk. These two characteristics also mean that deposits are typically the main source of funding for banks, especially for smaller institutions with limited access to wholesale funding markets. Third, non-deposit creditors are generally better placed than most depositors to assess and manage risk. Providing equivalent protection arrangements for non-deposit creditors would weaken market discipline and increase moral hazard.

Depositor Protection in Australia, Grant Turner, RBA Bulletin December Quarter 2011 (p45)

For a more technical discussion of these arguments I can recommend a paper by Gary Gorton and George Pennacchi titled “Financial Intermediation and Liquidity Creation” that I wrote about in this post.

Deposit preference potentially strengthens market discipline

I argued above that deposit preference potentially strengthens market discipline by transferring risk to debt and equity investors who have the skills to assess the risk, are paid a risk premium for doing so and, equally as importantly, the capacity to absorb the downside should a bank get into trouble. I recognise of course that this argument is strongest for the larger ADIs which have substantial layers of senior and subordinated debt that help ensure that deposits are materially insulated from bank risk. The capacity to bail-in a layer of this funding, independent of the conventional liquidation process, further adds to the protection of depositors while concentrating the role of market discipline where it belongs.

This market discipline role is one of the chief reasons I think “bail-in” adds to the resilience of the system in ways that higher equity requirements do not. The “skin in the game” these investors have is every bit as real as that the equity investors do, but they have less incentive to tolerate excessive or undisciplined risk taking.

The market discipline argument is less strong for the smaller ADIs which rely on deposits for a greater share of their funding but these entities account for a smaller share of bank deposits and can be liquidated if required with less disruption with the assistance of the government guarantee. The government guarantee seems to be more valuable for these ADIs than it is for the larger ADIs which are subject to a greater level of self-insurance.

Deposit preference plus ex ante funding of the deposit guarantee favours the smaller ADI

Interestingly, the ex ante nature of the funding of the government guarantee means that the ADIs for which it is least valuable (the survivors in general and the larger ADI’s in particular) are also the ones that will be called upon to pay the levy to make good any shortfalls not covered by deposit preference. That is at odds with the principle of risk based pricing that features in the literature about deposit guarantees but arguably a reasonable subsidy that assists the smaller ADIs to compete with larger ADI that have the benefit of risk diversification and economies of scale.

Summing up

If you want to dig deeper into this question, I have summarised the technical detail of the Australian deposit protection arrangements here. It is a little dated now but I can also recommend the article by Grant Turner published in the RBA Bulletin (December 2011) titled “Depositor Protection in Australia” which I quoted from above.

As always, it is entirely possible that I am missing something – if so let me know.

Tony – From The Outside

Adair Turner makes the case for “Monetary Finance”

This link takes you to an interesting post by Adair Turner on the limits of “monetary policy” (both conventional and the unconventional negative interest rate variety) and the potential use of “monetary finance”. Turner defines Monetary Finance as running a fiscal deficit (or higher deficit than would otherwise be the case) which is not financed by the issue of interest-bearing debt, but instead financed by an increase in the monetary base (i.e. by increasing the irredeemable non-interest bearing liabilities of the government/central bank.

I am probably over simplifying but, crudely stated, I think this is colloquially referred to as printing money and conventionally deemed to be a bad thing. So it is especially interesting seeing someone who was at the heart of the central banking world making the case. The post strikes a balance between the extremes of :

– there are no limits to what governments want to finance; and

– printing money = hyperinflation = the road to ruin.

I recommend you read his post in full but this extract gives you a flavour of the key message (or at least the one that I took away).

“So, on close inspection, all apparent technical objections to monetary finance dissolve. There is no doubt that monetary finance is technically feasible and that wise fiscal and monetary authorities could choose just the “right” amount.

The crucial issue is whether politicians can be trusted to be wise. Most central bankers are skeptical, and fear that monetary finance, once openly allowed, would become excessive. Indeed, for many, the knowledge that it is possible is a dangerous forbidden fruit which must remain taboo.

They may be right: the best policy may be to provide monetary finance while denying the fact. Governments can run large fiscal deficits. Central banks can make these fundable at close to zero rates. And these operations might be reversed if future rates of economic growth and inflation are higher than currently anticipated. If not, they will become permanent. But nobody needs to acknowledge that possibility in advance.”

I don’t agree with everything he writes but Turner is to my mind one of the more thoughtful commentators on banking, economics and finance. His resume includes being the head of the UK Financial Services Authority during the GFC. A book he wrote in 2015 titled “Between Debt and the Devil: Money, Credit and Fixing Global Finance” is also on my recommended reading list.

Tony (From the Outside)

Digital money – FT Alphaville

FT Alphaville is one of my go to sources for information and insight. The Alphaville post flagged below discusses the discussion paper recently released by the Bank of England on the pros and cons of a Central Bank Digital Currency. It is obviously a technical issue but worth at least scanning if you have any interest in banking and ways in which the concept of “money” may be evolving.

Read on ftalphaville.ft.com/2020/03/12/1584053069000/Digital-stimulus/

The rise of digital money

Given the central role that money plays in our economy, understanding how the rise of digital money will play out is becoming increasingly important. There is a lot being written on this topic but today’s post is simply intended to flag a paper titled “The Rise of Digital Money” that is one of the more useful pieces of analysis that I have come across. The paper is not overly long (20 pages) but the authors (Tobias Adrian and Tommaso Mancini-Griffoli) have also published a short summary of the paper here on the VOX website maintained by the Centre for Economic Policy Research.

Part of the problem with thinking about the rise of digital money is being clear about how to classify the various forms. The authors offer the following framework that they refer to as a Money Tree.

Adrian, T, and T Mancini-Griffoli (2019), “The rise of digital currency”, IMF Fintech Note 19/01.

This taxonomy identifies four key features that distinguish the various types of money (physical and digital):

  1. Type – is it a “claim” or an “object”?
  2. Value – is it the “unit of account” employed in the financial system, a fixed value in that unit of account, or a variable value?
  3. Backstop – if there is a fixed value redemption, is that value “backstopped” by the government or does it rely solely on private mechanisms to support the fixed exchange rate?
  4. Technology – centralised or decentralised?

Using this framework, the authors discuss the rise of stablecoins

“Adoption of new forms of money will depend on their attractiveness as a store of value and means of payment. Cash fares well on the first count, and bank deposits on both. So why hold stablecoins? Why are stablecoins taking off? Why did USD Coin recently launch in 85 countries,1 Facebook invest heavily in Libra, and centralised variants of the stablecoin business model become so widespread? Consider that 90% of Kenyans over the age of 14 use M-Pesa and the value of Alipay and WeChat Pay transactions in China surpasses that of Visa and Mastercard worldwide combined.

The question is all the more intriguing as stablecoins are not an especially stable store of value. As discussed, they are a claim on a private institution whose viability could prevent it from honouring its pledge to redeem coins at face value. Stablecoin providers must generate trust through the prudent and transparent management of safe and liquid assets, as well as sound legal structures. In a way, this class of stablecoins is akin to constant net asset value funds which can break the buck – i.e. pay out less than their face value – as we found out during the global financial crisis. 

However, the strength of stablecoins is their attractiveness as a means of payment. Low costs, global reach, and speed are all huge potential benefits. Also, stablecoins could allow seamless payments of blockchain-based assets and can be embedded into digital applications by an active developer community given their open architecture, as opposed to the proprietary legacy systems of banks. 

And, in many countries, stablecoins may be issued by firms benefitting from greater public trust than banks. Several of these advantages exist even when compared to cutting-edge payment solutions offered by banks called fast-payments.2 

But the real enticement comes from the networks that promise to make transacting as easy as using social media. Economists beware: payments are not the mere act of extinguishing a debt. They are a fundamentally social experience tying people together. Stablecoins are better integrated into our digital lives and designed by firms that live and breathe user-centric design. 

And they may be issued by large technology firms that already benefit from enormous global user bases over which new payment services could spread like wildfire. Network effects – the gains to a new user growing exponentially with the number of users – can be staggering. Take WhatsApp, for instance, which grew to nearly 2 billion users in ten years without any advertisement, based only on word of mouth!”

“The rise of digital currency”, Tobias Adrian, Tommaso Mancini-Griffoli 09 September 2019 – Vox CEPR Policy Portal

The authors then list the risks associated with the rise of stablecoins:

  1. The potential disintermediation of banks
  2. The rise of new monopolies
  3. The threat to weak currencies
  4. The potential to offer new opportunities for money laundering and terrorist financing
  5. Loss of “seignorage” revenue
  6. Consumer protection and financial stability

These risks are not dealt with in much detail. The potential disintermediation of banks gets the most attention (the 20 page paper explores 3 scenarios for how the disintermediation risk might play out).

The authors conclude with a discussion of what role central banks play in the rise of digital currency. They note that many central banks are exploring the desirability of stepping into the game and developing a Central Bank Digital Currency (CBDC) but do not attempt to address the broader question of whether the overall idea of a CBDC is a good one. They do however explore how central banks could work with stablecoin providers to develop a “synthetic” form of central bank digital currency by requiring the “coins” to be backed with central bank reserves.

This is effectively bringing the disrupters into the fold by turning them into a “narrow bank”. Izabella Kaminska (FT Alphaville) has also written an article on the same issue here that is engagingly titled “Why dealing with fintechs is a bit like dealing with pirates”.

The merits of narrow banking lie outside the scope of this post but it a topic with a very rich history (search on the term “Chicago Plan”) and one that has received renewed support in the wake of the GFC. Mervyn King (who headed the Bank of England during the GFC), for example, is one prominent advocate.

Hopefully you found this useful, if not my summary then at least the links to some articles that have helped me think through some of the issues.

Tony

Alternative monetary and financial systems

We probably tend to take the monetary and financial system we have today for granted, somewhat like the air we breathe. I was also challenged during the week to describe a non-money future and my response was judged a failure to look outside the square. The best I could offer was to note that Star Trek imagines a society in which unlimited cheap energy coupled with replicators has made money redundant.

By chance, I came across a couple of articles in recent weeks that offer interesting perspectives on what money is and its role in the economy.

One was by Tyler Cowen marking the 75th anniversary of Bretton Wood’s but more imaginatively subtitled “Every era’s monetary and financial institutions are unimaginable until they are real”. The other was an interview with a German philosopher Stefan Heidenreich discussing his book titled “Money: For a Non-money Economy”.

The Bretton Woods agreement of course is not the system we have today but Cowen makes the point that the system we operate under today would appear equally unlikely to previous generations:

“Currencies are fiat, the ties to gold are gone, and most exchange rates for the major currencies are freely floating, with periodic central bank intervention to manipulate exchange rates. For all the criticism it receives, this arrangement has also proved to be a viable global monetary order, and it has been accompanied by an excellent overall record for global growth.

Yet this fiat monetary order might also have seemed, to previous generations of economists, unlikely to succeed. Fiat currencies were associated with the assignat hyperinflations of the French Revolution, the floating exchange rates and competitive devaluations of the 1920s were not a success, and it was hardly obvious that most of the world’s major central banks would pursue inflation targets of below 2%. Until recent times, the record of floating fiat currencies was mostly disastrous”

Cowen’s main message is that the lesson of history suggests that it is brave to assume that the monetary and financial institution status quo will hold forever – so what comes next?

This brings us to Stefan Heidenreich.

“Stefan Heidenreich believes that some day, money will seem like an ancient religion. In his recent book Money: For a Non-money Economy, the German philosopher and media theorist speculates on how the money-based global economy could soon transition to an entirely different system based on the algorithmic matching of goods and services. Such a system could match people with what they need at a given moment without relying on the concept of a stable, universal price — and, just possibly, do away with the vast inequities caused by the market.

If you find the idea of an economy without money hard to imagine, you’re not alone. As the saying goes, it’s easier to imagine the end of the world than the end of capitalism. But that very difficulty proves Heidenreich’s main point: We have to imagine what may sound like wild possibilities now in order to steer the future before it’s upon us. Getting rid of money could lead to what he calls a “leftist utopia” of equal distribution — or it could enable mass surveillance and algorithmic control on a whole new scale. Faced with the second option, Heidenreich says, we have no choice but to try to envision the first.”

“The Economy of the Future Won’t Rely on Money” Elvia Wilk (Medium 30 November 2018) https://medium.com/s/story/the-economy-of-the-future-wont-rely-on-money-5a703e0ad30b

It is not obvious to me that Heidenreich’s “matching” proposal provides a workable alternative to what we have today but that is not the point. The bigger point raised by both Cowen and Heidenreich is that what we have today is unlikely to be the system that governs our economic interactions in 50 years time so what is the alternative?

Tony

Deposit insurance and moral hazard

Depositors tend to be a protected species

It is generally agreed that bank deposits have a privileged position in the financial system. There are exceptions to the rule such as NZ which, not only eschews deposit insurance, but also the practice of granting deposits a preferred (or super senior) claim on the assets of the bank. NZ also has a unique approach to bank resolution which clearly includes imposing losses on bank deposits as part of the recapitalisation process. Deposit insurance is under review in NZ but it is less clear if that review contemplates revisiting the question of deposit preference.

The more common practice is for deposits to rank at, or near, the top of the queue in their claim on the assets of the issuing bank. This preferred claim is often supported by some form of limited deposit insurance (increasingly so post the Global Financial Crisis of 2008). An assessment of the full benefit has to consider the cost of providing the payment infrastructure that bank depositors require but the issuing bank benefits from the capacity to raise funds at relatively low interest rates. The capacity to raise funding in the form of deposits also tends to mean that the issuing banks will be heavily regulated which adds another layer of cost.


The question is whether depositors should be protected

I am aware of two main arguments for protecting depositors:

  • One is to protect the savings of financially unsophisticated individuals and small businesses.
  • The other major benefit relates to the short-term, on-demand, nature of deposits that makes them convenient for settling transactions but can also lead to a ‘bank run’.

The fact is that retail depositors are simply not well equipped to evaluate the solvency and liquidity of a bank. Given that even the professionals can fail to detect problems in banks, it is not clear why people who will tend to lie at the unsophisticated end of the spectrum should be expected to do any better. However, the unsophisticated investor argument by itself is probably not sufficient. We allow these individuals to invest in the shares of banks and other risky investments so what is special about deposits.

The more fundamental issue is that, by virtue of the way in which they function as a form of money, bank deposits should not be analysed as “investments”. To function as money the par value of bank deposits must be unquestioned and effectively a matter of faith or trust. Deposit insurance and deposit preference are the tools we use to underwrite the safety and liquidity of bank deposits and this is essential if bank deposits are to function as money. We know the economy needs money to facilitate economic activity so if bank deposits don’t perform this function then you need something else that does. Whatever the alternative form of money decided on, you are still left with the core issue of how to make it safe and liquid.

Quote
“The capacity of a financial instrument like a bank deposit to be accepted and used as money depends on the ability of uninformed agents to trade it without fear of loss; i.e. the extent to which the value of the instrument is insulated from any adverse information about the counterparty”

Gary Gorton and George Pennacchi “Financial Intermediaries and Liquidity Creation”

I recognise that fintech solutions are increasingly offering alternative payment mechanisms that offer some of the functions of money but to date these still ultimately rely on a bank with a settlement account at the central bank to function. This post on Alphaville is worth reading if you are interested in this area of financial innovation. The short version is that fintechs have not been able to create new money in the way banks do but this might be changing.

But what about moral hazard?

There is an argument that depositors should not be a protected class because insulation from risk creates moral hazard.

While government deposit insurance has proven very successful in protecting banks from runs, it does so at a cost because it leads to moral hazard (Santos, 2000, p. 8). By offering a guarantee that depositors are not subject to loss, the provider of deposit insurance bears the risk that they would otherwise have borne.

According to Dr Sam Wylie (2009, p. 7) from the Melbourne Business School:

“The Government eliminates the adverse selection problem of depositors by insuring them against default by the bank. In doing so the Government creates a moral hazard problem for itself. The deposit insurance gives banks an incentive to make higher risk loans that have commensurately higher interest payments. Why?, because they are then betting with taxpayer’s money. If the riskier loans are repaid the owners of the bank get the benefit. If not, and the bank’s assets cannot cover liabilities, then the Government must make up the shortfall”

Reconciling Prudential Regulation with Competition, Pegasus Economics, May 2019 (p17)

A financial system that creates moral hazard is clearly undesirable but, for the reasons set out above, it is less clear to me that bank depositors are the right set of stakeholders to take on the responsibility of imposing market discipline on banks. There is a very real problem here but requiring depositors to take on this task is not the answer.

The paper by Gorton and Pennacchi that I referred to above notes that there is a variety of ways to make bank deposits liquid (i.e. insensitive to adverse information about the bank) but they argue for solutions where depositors have a sufficiently deep and senior claim on the assets of the bank that any volatility in their value is of no concern. This of course is what deposit insurance and giving deposits a preferred claim in the bank loss hierarchy does. Combining deposit insurance with a preferred claim on a bank’s assets also means that the government can underwrite deposit insurance with very little risk of loss.

It is also important I think to recognise that deposit preference moves the risk to other parts of the balance sheet that are arguably better suited to the task of exercising market discipline. The quote above from Pegasus Economics focussed on deposit insurance and I think has a fair point if the effect is simply to move risk from depositors to the government. That is part of the reason why I think that deposit preference, combined with how the deposit insurance is funded, are also key elements of the answer.

Designing a banking system that addresses the role of bank deposits as the primary form of money without the moral hazard problem

I have argued that the discussion of moral hazard is much more productive when the risk of failure is directed at stakeholders who have the expertise to monitor bank balance sheets, the capacity to absorb the risk and who are compensated for undertaking this responsibility. If depositors are not well suited to the market discipline task then who should bear the responsibility?

  • Senior unsecured debt
  • Non preferred senior debt (Tier 3 capital?)
  • Subordinated debt (i.e. Tier 2 capital)
  • Additional Tier 1 (AT1)
  • Common Equity Tier 1 (CET1)

There is a tension between liquidity and risk. Any security that is risky may be liquid during normal market conditions but this “liquidity” cannot be relied on under adverse conditions. Senior debt can in principle be a risky asset but most big banks will also aim to be able to issue senior debt on the best terms they can achieve to maximise liquidity. In practice, this means that big banks will probably aim for a Long Term Senior Debt Rating that is safely above the “investment grade” threshold. Investment grade ratings offer not just the capacity top issue at relatively low credit spreads but also, and possibly more importantly, access to a deeper and more reliable pool of funding.

Cheaper funding is nice to have but reliable access to funding is a life and death issue for banks when they have to continually roll over maturing debt to keep the wheels of their business turning. This is also the space where banks can access the pools of really long term funding that are essential to meet the liquidity and long term funding requirements that have been introduced under Basel III.

The best source of market discipline probably lies in the space between senior debt and common equity

I imagine that not every one will agree with me on this but I do not see common equity as a great source of market discipline on banks. Common equity is clearly a risky asset but the fact that shareholders benefit from taking risk is also a reason why they are inclined to give greater weight to the upside than to the downside when considering risk reward choices. As a consequence, I am not a fan of the “big equity” approach to bank capital requirements.

In my view, the best place to look for market discipline and the control of moral hazard in banking lies in securities that fill the gap between senior unsecured debt and common equity; i.e. non-preferred senior debt, subordinated debt and Additional Tier 1. I also see value in having multiple layers of loss absorption as opposed to one big homogeneous layer of loss absorption. This is partly because it can be more cost effective to find different groups of investors with different risk appetites. Possibly more important is that multiple layers offer both the banks and supervisors more flexibility in the size and impact of the way these instruments are used to recapitalise the bank.

Summing up …

I have held off putting this post up because I wanted the time to think through the issues and ensure (to the best of my ability) that I was not missing something. There remains the very real possibility that I am still missing something. That said, I do believe that understanding the role that bank deposits play as the primary form of money is fundamental to any complete discussion of the questions of deposit insurance, deposit preference and moral hazard in banking.

Tony

What is the value of information in the money market?

“Debt and institutions dealing with debt have two faces: a quiet one and a tumultuous one …. The shift from an information-insensitive state where liquidity and trust prevails because few questions need to be asked, to an information-sensitive state where there is a loss of confidence and a panic may break out is part of the overall system: the calamity is a consequence of the quiet. This does not mean that one should give up on improving the system. But in making changes, it is important not to let the recent crisis dominate the new designs. The quiet, liquid state is hugely valuable.”

Bengt Holmstrom (2015)

The quote above comes from an interesting paper by Bengt Holmstrom that explores the ways in which the role money markets play in the financial system is fundamentally different from that played by stock markets. That may seem like a statement of the obvious but Holmstrom argues that some reforms of credit markets which based on the importance of transparency and detailed disclosure are misconceived because they do not reflect these fundamental differences in function and mode of operation.

Holmstrom argues that the focus and purpose of stock markets is price discovery for the purpose of allocating risk efficiently. Money markets, in contrast are about obviating the need for price discovery in order to enhance the liquidity of the market. Over-collateralisation is one of the features of the money market that enable deep, liquid trading to occur without the need to understand the underlying risk of the assets that are being funded .

 “The design of money market policies and regulations should recognise that money markets are very different from stock markets. Lessons from the latter rarely apply to the former, because markets for risk-sharing and markets for funding have their own separate logic. The result is two coherent systems with practices that are in almost every respect polar opposites.”

From “Understanding the role of debt in the financial system” Bengt Holmstrom (BIS Working Papers No 479 – January 2015)

Holmstrom appears to have written the paper in response to what he believes are misconceived attempts to reform credit markets in the wake of the recent financial crisis. These reforms have often drawn on insights grounded in our understanding of stock markets where information and transparency are key requirements for efficient price discovery and risk management. His paper presents a perspective on the logic of credit markets and the structure of debt contracts that highlights the information insensitivity of debt. This perspective explains among other things why he believes that information insensitivity is the natural and desired state of the money markets.

Holmstrom notes that one of the puzzles of the GFC was how people traded so many opaque instruments with a seeming ignorance of their real risk. There is a tendency to see this as a conspiracy by bankers to confuse and defraud customers which in turn has prompted calls to make money market instruments more transparent. While transparency and disclosure is essential for risk pricing and allocation, Holmstrom argues that this is not the answer for money markets because they operate on different principles and serve a different function.

 “I will argue that a state of “no questions asked” is the hallmark of money market liquidity; that this is the way money markets are supposed to look when they are functioning well.”

“Among economists, the mistake is to apply to money markets the lessons and logic of stock markets.”

“The key point I want to communicate today is that these two markets are built on two entirely different, one could say diametrically opposite, logics. Ultimately, this is because they serve two very different purposes. Stock markets are in the first instance aimed at sharing and allocating aggregate risk. To do that effectively requires a market that is good at price discovery.

 “But the logic behind transparency in stock markets does not apply to money markets. The purpose of money markets is to provide liquidity for individuals and firms. The cheapest way to do so is by using over-collateralised debt that obviates the need for price discovery. Without the need for price discovery the need for public transparency is much less. Opacity is a natural feature of money markets and can in some instances enhance liquidity, as I will argue later.”

“Why does this matter? It matters because a wrong diagnosis of a problem is a bad starting point for remedies. We have learned quite a bit from this crisis and we will learn more. There are things that need to be fixed. But to minimise the chance of new, perhaps worse mistakes, we need to analyse remedies based on the purpose of liquidity provision. In particular, the very old logic of collateralised debt and the natural, but sometimes surprising implications this has for how information and risk are handled in money markets, need to be properly appreciated.”

There is a section of the paper titled “purposeful opacity” which, if I understood him correctly, seemed to extend his thesis on the value of being able to trade on an “information insensitive” basis to argue that “opacity” in the debt market is something to be embraced rather than eliminated. I struggled with embracing opacity in this way but that in no way diminishes the validity of the distinction he draws between debt and equity markets.

The other useful insight was the way in which over-collateralistion (whether explicit or implicit) anchors the liquidity of the money market. His discussion of why the sudden transition from a state in which the creditworthiness of a money market counter-party is taken for granted to one in which doubt emerges also rings true.

The remainder of this post mostly comprises extracts from the paper that offer more detail on the point I have summarised above. The paper is a technical one but worth the effort for anyone interested in the question of how banks should finance themselves and the role of debt in the financial system.

Money markets versus stock markets

Holmstrom argues that each system displays a coherent internal logic that reflects its purpose but these purposes are in many respects polar opposites.

Stock markets are primarily about risk sharing and price discovery. As a consequence, these markets are sensitive to information and value transparency. Traders are willing to make substantial investments to obtain this information. Liquidity is valuable but equity investors will tend to trade less often and in lower volumes than debt markets.

Money markets, in contrast, Holmstrom argues are primarily about liquidity provision and lending. The price discovery process is much simpler but trading is much higher volume and more urgent.

“The purpose of money markets is to provide liquidity. Money markets trade in debt claims that are backed, explicitly or implicitly, by collateral.

 “People often assume that liquidity requires transparency, but this is a misunderstanding. What is required for liquidity is symmetric information about the payoff of the security that is being traded so that adverse selection does not impair the market. Without symmetric information adverse selection may prevent trade from taking place or in other ways impair the market (Akerlof (1970)).”

“Trading in debt that is sufficiently over-collateralised is a cheap way to avoid adverse selection. When both parties know that there is enough collateral, more precise private information about the collateral becomes irrelevant and will not impair liquidity.”

The main purpose of stock markets is to share and allocate risk … Over time, stock markets have come to serve other objectives too, most notably governance objectives, but the pricing of shares is still firmly based on the cost of systemic risk (or a larger number of factors that cannot be diversified). Discovering the price of systemic risk requires markets to be transparent so that they can aggregate information efficiently.     

Purposeful opacity

“Because debt is information-insensitive … traders have muted incentives to invest in information about debt. This helps to explain why few questions were asked about highly rated debt: the likelihood of default was perceived to be low and the value of private information correspondingly small.”

 Panics: The ill consequences of debt and opacity

“Over-collateralised debt, short debt maturities, reference pricing, coarse ratings, opacity and “symmetric ignorance” all make sense in good times and contribute to the liquidity of money markets. But there is a downside. Everything that adds to liquidity in good times pushes risk into the tail. If the underlying collateral gets impaired and the prevailing trust is broken, the consequences may be cataclysmic”

“The occurrence of panics supports the informational thesis that is being put forward here. Panics always involve debt. Panics happen when information-insensitive debt (or banks) turns into information-sensitive debt … A regime shift occurs from a state where no one feels the need to ask detailed questions, to a state where there is enough uncertainty that some of the investors begin to ask questions about the underlying collateral and others get concerned about the possibility”

These events are cataclysmic precisely because the liquidity of debt rested on over-collateralisation and trust rather than a precise evaluation of values. Investors are suddenly in the position of equity holders looking for information, but without a market for price discovery. Private information becomes relevant, shattering the shared understanding and beliefs on which liquidity rested (see Morris and Shin (2012) for the general mechanism and Goldstein and Pauzner (2005) for an application to bank runs).

Would transparency have helped contain the contagion?

“A strong believer in the informational efficiency of markets would argue that, once trading in credit default swaps (CDS) and then the ABX index began, there was a liquid market in which bets could be made both ways. The market would find the price of systemic risk based on the best available evidence and that would serve as a warning of an imminent crisis. Pricing of specific default swaps might even impose market discipline on the issuers of the underlying debt instruments”

 Shadow banking

 “The rapid growth of shadow banking and the use of complex structured products have been seen as one of the main causes of the financial crisis. It is true that the problems started in the shadow banking system. But before we jump to the conclusion that shadow banking was based on unsound, even shady business practices, it is important to try to understand its remarkable expansion. Wall Street has a hard time surviving on products that provide little economic value. So what drove the demand for the new products?”

 “It is widely believed that the global savings glut played a key role. Money from less developed countries, especially Asia, flowed into the United States, because the US financial system was perceived to be safe … More importantly, the United States had a sophisticated securitisation technology that could activate and make better use of collateral … Unlike the traditional banking system, which kept mortgages on the banks’ books until maturity, funding them with deposits that grew slowly, the shadow banking system was highly scalable. It was designed to manufacture, aggregate and move large amounts of high-quality collateral long distances to reach distant, sizable pools of funds, including funds from abroad.”

“Looking at it in reverse, the shadow banking system had the means to create a lot of “parking space” for foreign money. Securitisation can manufacture large amounts of AAA-rated securities provided there is readily available raw material, that is, assets that one can pool and tranche”

“I am suggesting that it was an efficient transportation network for collateral that was instrumental in meeting the global demand for safe parking space.”

 “The distribution of debt tranches throughout the system, sliced and diced along the way, allowing contingent use of collateral”

“Collateral has been called the cash of shadow banking (European repo council (2014)). It is used to secure large deposits as well as a host of derivative transactions such as credit and interest rate swaps.”  

There is a relatively recent, but rapidly growing, body of theoretical research on financial markets where the role of collateral is explicitly modelled and where the distinction between local and global collateral is important

“Viewed through this theoretical lens, the rise of shadow banking makes perfectly good sense. It expanded in response to the global demand for safe assets. It improved on traditional banking by making collateral contingent on need and allowing it to circulate faster and attract more distant capital. In addition, securitisation created collateral of higher quality (until the crisis, that is) making it more widely acceptable. When the crisis hit, bailouts by the government, which many decry, were inevitable. But as just discussed, the theory supports the view that bailouts were efficient even as an ex ante policy (if one ignores potential moral hazard problems). Exchanging impaired collateral for high-quality government collateral, as has happened in the current crisis (as well as historically with clearing houses), can be rationalised on these grounds.”

 Some policy implications

 A crisis ends only when confidence returns. This requires getting back to the no-questions-asked state ….

Transparency would likely have made the situation worse

“By now, the methods out of a crisis appear relatively well understood. Government funds need to be committed in force (Geithner (2014)). Recapitalisation is the only sensible way out of a crisis. But it is much less clear how the banking system, and especially shadow banking, should be regulated to reduce the chance of crisis in the first place.  The evidence from the past panic suggests that greater transparency may not be that helpful.”

“The logic of over-capitalisation in money markets leads me to believe that higher capital requirements and regular stress tests is the best road for now.”

“Transparency can provide some market discipline and give early warning of trouble for individual banks. But it may also lead to strategic behaviour by management. The question of market discipline is thorny. In good times market discipline is likely to work well. The chance that a bank that is deemed risky would trigger a panic is non-existent and so the bank should pay the price for its imprudence. In bad times the situation is different. The failure of a bank could trigger a panic. In bad times it would seem prudent to be less transparent with the stress tests (for some evidence in support of this dichotomy, see Machiavelli (1532)).”

“On money, debt, trust and central banking”

Is the title of an interesting paper by Claudio Borio (Head of the Monetary and Economic Department at the BIS). This link will take you to the paper but my post offers a short summary of what I took away from it.

Overview of the paper

Borio’s examination of the properties of a well functioning monetary system:

  • stresses the importance of the role trust plays in this system and of the institutions needed to secure that trust.
  • explores in detail the ways in which these institutions help to ensure the price and financial stability that is critical to nurturing and maintaining that trust.
  • focuses not just on money but also the transfer mechanisms to execute payments (i.e. the “monetary system”)

“My focus will be the on the monetary system, defined technically as money plus the transfer mechanisms to execute payments. Logically, it makes little sense to talk about one without the other. But payments have too often been taken for granted in the academic literature, old and new. In the process, we have lost some valuable insights.”

Borio: Page 1

In the process, he addresses several related questions, such as

  • the relationship between money and debt,
  • the viability of cryptocurrencies as money,
  • money neutrality, and
  • the nexus between monetary and financial stability.

Borio highlights three key points he wants you to take away from his paper

First, is the fundamental way in which the monetary system relies on trust and equally importantly the role that institutions, the central bank in particular, play in ensuring there is trust in the system. At the technical level, people need to trust that the object functioning as money will be generally accepted and that payments will be executed but it also requires trust that the system will deliver price and financial stability in the long run.

Second, he draws attention to the “elasticity of credit” (i.e. the extent to which the system allows credit to expand) as a key concept for understanding how the monetary system works. Elasticity of credit, he argues, is essential for the day to day operations of the payment system but allowing too much credit expansion can cause serious economic damage in the long run.

Third, the need to understand the ways in price and financial stability are different but inexorably linked. As concepts, they are joined at the hip: both embody the trust that sustains the monetary system. But the underlying processes required to achieve these outcomes differ, so that there can be material tensions in the short run.

These are not necessarily new insights to anyone who has being paying attention to the questions Borio poses above, but the paper does offer a good, relatively short, overview of the issues. I particularly liked the way Borio

  • presented the role elasticity of credit plays in both the short and long term functioning of the economy and how the tension between the short and long term is managed,
  • covered the relationship between money, debt and trust (“we can think of money as an especially trustworthy type of debt”), and
  • outlined how and why the monetary system should be seen, not as an “outer facade” but rather as a “cornerstone of an economy”

The rest of this post contains more detailed notes on some, but not all, of the issues covered in the paper.

Elements of a well functioning monetary system

The standard definition of money is based on its functions as
1) Unit of account
2) Means of payment
3) Store of value

Borio expands the focus to encompass the “monetary system”as a whole, introducing two additional elements. Firstly the need to consider the mechanisms the system uses to transfer the means of payment and settle transactions. Secondly, the ways in which the integrity of the chosen form of money as a store of value is protected.

” In addition, compared with the traditional focus on money as an object, the definition crucially extends the analysis to the payment mechanisms. In the literature, there has been a tendency to abstract from them and assume they operate smoothly in the background. I believe this is one reason why money is often said to be a convention …. But money is much more than a convention; it is a social institution (eg Giannini (2011)). It is far from self-sustaining. Society needs an institutional infrastructure to ensure that money is widely accepted, transactions take place, contracts are fulfilled and, above all, agents can count on that happening”

Borio: Page 3

The day to day operation of the monetary system

Borio highlights two aspects of the day to day operations of the monetary system.

  1. The need for an elastic supply of the means of payment
  2. The need for an elastic supply of bank money more generally

In highlighting the importance of the elasticity of credit, he also draws attention to “the risk of overestimating the distinction between credit (debt) and money”.

The central banks’ elastic supply of the means of payment is essential to ensure that (i) transactions are settled in the interbank market and (ii) the interest rate is controlled.

“To smooth out interbank settlement, the provision of central bank credit is key. The need for an elastic supply to settle transactions is most visible in the huge amounts of intraday credit central banks supply to support real-time gross settlement systems – a key way of managing risks in those systems (Borio (1995)).”

Borio: Page 5
“…we can think of money as an especially trustworthy type of debt”

Put differently, we can think of money as an especially trustworthy type of debt. In the case of bank deposits, trust is supported by central bank liquidity, including as lender of last resort, by the regulatory and supervisory framework and varieties of deposit insurance; in that of central bank reserves and cash, by the sovereign’s power to tax; and in both cases, by legal arrangements, way beyond legal tender laws, and enshrined in market practice.

Borio: Page 9

Once you understand the extent to which our system of money depends on credit relationship you understand the extent to which trust is a core feature which should not be taken for granted. The users of the monetary system are relying on some implied promises that underpin their trust in it.

“Price and financial instability amount to broken promises.”

Borio: Page 11

While the elasticity of money creation oils the wheels of the payment system on a day to day basis, it can be problematic over long run scenarios where too much elasticity can lead to financial instability. Some degree of elasticity is important to keep the wheels of the economy turning but too much can be a problem because the marginal credit growth starts to be used for less productive or outright speculative investment.

The relationship between price and financial stability

While, as concepts, price and financial stability are joined at the hip, the processes behind the two differ. Let’s look at this issue more closely


The process underpinning financial instability hinges on how “elastic” the monetary system is over longer horizons, way beyond its day-to-day operation. Inside credit creation is critical. At the heart of the process is the nexus between credit creation, risk-taking and asset prices, which interact in a self-reinforcing fashion generating possibly disruptive financial cycles (eg Borio (2014)). The challenge is to ensure that the system is not excessively elastic drawing on two monetary system anchors. One operates on prices – the interest rate and the central bank’s reaction function … The other operates on quantities: bank regulatory requirements, such as those on capital or liquidity, and the supervisory apparatus that enforces them.

Borio: Page 12

Given that the processes underlying price and financial stability differ, it is not surprising that there may be material tensions between the two objectives, at least in the near term. Indeed, since the early 1980s changes in the monetary system have arguably exacerbated such tensions by increasing the monetary system’s elasticity (eg Borio (2014)). This is so despite the undoubted benefits of these changes for the world economy. On the one hand, absent a sufficiently strong regulatory and supervisory apparatus – one of the two anchors – financial liberalisation, notably for banks, has provided more scope for outsize financial cycles. On the other hand, the establishment of successful monetary policy frameworks focused on near-term inflation control has meant that there was little reason to raise interest rates – the second anchor – since financial booms took hold as long as inflation remained subdued. And in the background, with the globalisation of the real side of the economy putting persistent downward pressure on inflation while at the same time raising growth expectations, there was fertile ground for financial imbalances to take root in.

Borio: Page 16

Borio concludes that the monetary system we have is far from perfect but it is better than the alternatives

Borio concludes that the status quo, while far from perfect, is worth persisting with. He rejects the cryptocurrency path but does not explicitly discuss other radical options such as the one proposed by Mervyn King, in his book “The End of Alchemy”. The fact that he believes “… the distinction between money and debt is often overplayed” could be interpreted as an indirect rejection of the variations on the Chicago Plan that have recently reentered public debate. It would have been interesting to see him address these alternative monetary system models more directly.

In Borio’s own words ….

 The monetary system is the cornerstone of an economy. Not an outer facade, but its very foundation. The system hinges on trust. It cannot survive without it, just as we cannot survive without the oxygen we breathe. Building trust to ensure the system functions well is a daunting challenge. It requires sound and robust institutions. Lasting price and financial stability are the ultimate prize. The two concepts are inextricably linked, but because the underlying processes differ, in practice price and financial stability have often been more like uncomfortable bedfellows than perfect partners. The history of our monetary system is the history of the quest for that elusive prize. It is a journey with an uncertain destination. It takes time to gain trust, but a mere instant to lose it. The present system has central banks and a regulatory/supervisory apparatus at its core. It is by no means perfect. It can and must be improved.55  But cryptocurrencies, with their promise of fully decentralised trust, are not the answer. 

Paraphrasing Churchill’s famous line about democracy, “the current monetary system is the worst, except for all those others that have been tried from time to time”. 


Page 18

The topic is not for everyone, but I found the paper well worth reading.

Tony

“The Origin of Financial Crises” by George Cooper

There are a lot of books on the topic of financial crises but this one, written in 2008, stand the test of time. At the very least, it offers a useful introduction to Minsky’s Financial Instability Hypothesis. There is also an interesting discussion of the alternative approaches adopted by central banks to the problem of financial stability.

George Cooper argues that our financial system is inherently unstable and that this tendency is accentuated by a combination of factors

  • The belief that market forces will tend to produce optimal allocations of capital, and
  • Monetary policy that seeks to smooth (and ideally eliminate) business cycle fluctuations in economic activity

Cooper draws heavily on Hyman Minsky’s Financial Instability Hypothesis (FIH) which he argues offers much better insight into the operation of the financial system than the  the Efficient Market Hypothesis (EMH) which tended to be the more influential driver of economic policy in the years preceding the Global Financial Crisis.

Cooper uses these competing theories to explore what makes prices within financial markets move. The EMH maintains that the forces of supply and demand will cause markets to move towards equilibrium and hence that we must look to external forces to understand unexpected shocks and crises. Minsky’s FIH, in contrast, argues that financial markets can be driven by internal forces into cycles of credit expansion and asset inflation followed by credit contraction and asset deflation.

Cooper identifies the following ways in which financial systems can become unstable

  • Markets characterised by supply constraints tend to experience price inflation which for a period of time can drive further increases in demand
  • Monetary policy which is oriented towards mitigating (and in some cases pre-empting) economic downturns can also amplify market instability (i.e. the Greenspan put makes the market less resilient in the long run)
  • Credit creation by private sector banks contributes to money supply growth; this in turn can facilitate growth in demand but there is no mechanism that automatically makes this growth consistent with the economy’s sustainable growth path

The point about some asset markets being prone to instability is particularly pertinent for banks that focus on residential property lending. Classical economic theory holds that increased prices should lead to increased supply and reduced demand but this simple equilibrium model does not necessarily work for property markets. Property buyers more often reason that they need to meet the market because it will only get more expensive if they wait. Many of them will have already seen this happen and regret not meeting the market price previously as they contemplate paying more to get a property that is not as nice as ones they underbid on. The capacity of home builders to respond to the price signal is frequently constrained by a myriad of factors and there is a long lead time when they do respond.

The argument Cooper makes rings very true for Australia and is very similar to the one that Adair Turner made in his book titled ”Between debt and the devil”. Cooper’s (and Minsky’s) argument that the pursuit of stability is not a desirable objective and that the system benefits from a modest amount of stress is similar to the argument made by Nassim Taleb in “Antifragility”.

Cooper also discusses the different philosophies that central banks bring to the challenge of managing financial stability. The dominant view is one that focuses on the risk that sees the management of inflation risk as a dominant concern while placing greater trust in the capacity of the market to self correct any instability. The European Central Bank, in contrast, seems to have placed less faith in the market and perhaps been closer to Minsky.

Some quotes from the book will give a sense of the ideas being discussed:

“Through its role in asset price cycles and profit generation, credit formation (borrowing money for either consumption or investment) lies at the heart of the financial market’s fundamental instability”.

“Hyman Minsky said that “stability creates instability” referring to our tendency to build up an unsustainable stock of debt in times of plenty only for that debt to then destroy the times of plenty”

“For a system as inherently unstable as the financial markets, we should not seek to achieve perfect stability; arguably it is this objective that has led to today’s problems. A more sustainable strategy would involve permitting, and at times encouraging, greater short-term cyclicality, using smaller, more-frequent downturns to purge the system of excesses”

“Credit creation is the foundation of the wealth-generation process; it is also the cause of financial instability. We should not let the merits of the former blind us to the risks of the latter.”

I have made some more detailed notes on the book here.

Tony

Worth Reading “The Money Formula” by Paul Wilmott and David Orrell.

The full title of this book, co-written by Paul Wilmott and David Orrell, is “The Money Formula: Dodgy Finance, Pseudo Science, and How Mathematicians Took over the Markets“. There are plenty of critiques of modelling and quantitative finance by outsiders throwing rocks but Wilmott is a quant and brings an insider’s technical knowledge to the question of what these tools can do, can’t do and perhaps most importantly should not be used to do. Consequently, the book offers a more nuanced perspective on the strengths and limitations of quantitative finance as opposed to the let’s scrap the whole thing school of thought. I have made some more detailed notes which follow the structure of the book but this post focuses on a couple of ideas I found especially interesting or useful.

I am not a quant so my comments should be read with that in mind but the core idea I took away is that, much as quants would want it otherwise, markets are not determined by fundamental laws, deterministic or probabilistic that allow risk to be measured with precision. These ideas work reasonably well within their “zone of validity” but a more complete answer (or model) has to recognise where the zones stop and uncertainty rules.  Wilmott and Orrell argue market outcomes are better thought of as the “emergent result of complex transactions”. The role of money in these emergent results is especially important, as is the capacity of models themselves to materially reshape the risk of the markets they are attempting to measure.

The Role of Money

Some quotes I have drawn from Chapter 8, will let the authors speak for themselves on the role of money …

Consider …. the nature of money. Standard economic definitions of money concentrate on its roles as a “medium of exchange,” a “store of value,” and a “unit of account.” Economists such as Paul Samuelson have focused in particular on the first, defining money as “anything that serves as a commonly accepted medium of exchange.” … ” Money is therefore not something important in itself; it is only a kind of token. The overall picture is of the economy as a giant barter system, with money acting as an inert facilitator.” (emphasis added)

“However … money is far more interesting than that, and actually harbors its own kind of lively, dualistic properties. In particular, it merges two things, number and value, which have very different properties:number lives in the abstract, virtual world of mathematics, while valued objects live in the real world. But money seems to be an active part of the system. So ignoring it misses important relationships. The tension between these contradictory aspects is what gives money its powerful and paradoxical qualities.” (Emphasis added)

The real and the virtual become blurred, in physics or in finance. And just as Newtonian theories break down in physics, so our Newtonian approach to money breaks down in economics. In particular, one consequence is that we have tended to take debt less seriously than we should. (emphasis added)

Instead of facing up to the intrinsically uncertain nature of money and the economy, relaxing some of those tidy assumptions, accepting that markets have emergent properties that resist reduction to simple laws, and building a new and more realistic theory of economics, quants instead glommed on to the idea that, when a system is unpredictable, you can just switch to making probabilistic predictions.” (emphasis added)

“The efficient market hypothesis, for example, was based on the mechanical analogy that markets are stable and perturbed randomly by the actions of atomistic individuals. This led to probabilistic risk-analysis tools such as VaR. However, in reality, the “atoms” are not independent, but are closely linked … The result is the non-equilibrium behaviour … observed in real markets. Markets are unpredictable not because they are efficient, but because of a financial version of the uncertainty principle.” (emphasis added)

 The Role of Models

Wilmott & Orrell devote a lot of attention to the ways in which models no longer just describe, but start to influence, the markets being modelled mostly by encouraging people to take on more risk based in part on a false sense of security …

“Because of the bankers’ insistence on treating complex finance as a university end-of-term exam in probability theory, many of the risks in the system are hidden. And when risks are hidden, one is led into a false sense of security. More risk is taken so that when the inevitable happens, it is worse than it could have been. Eventually the probabilities break down, disastrous events become correlated, the cascade of dominoes is triggered, and we have systemic risk …. None of this would matter if the numbers were small … but the numbers are huge” (Chapter 10 – emphasis added)

They see High Frequency Trading as the area likely to give rise to a future systemic crisis but also make a broader point about the tension between efficiency and resilience..

“With complex systems, there is usually a trade-off between efficiency and robustness …. Introducing friction into the system – for example by putting regulatory brakes on HFT – will slow the markets, but also make them more transparent and reliable. If we want a more robust and resilient system then we probably need to agree to forego some efficiency” (Chapter 10 – emphasis added)

The Laws of Finance

Wilmott and Orrell note the extent to which finance has attempted to identify laws which are analogous to the laws of physics and the ways in which these “laws” have proved to be more of a rough guide.

 “… the “law of supply and demand” …states that the market for a particular product has a certain supply, which tends to increase as the price goes up (more suppliers enter the market). There is also a certain demand for the product, which increases as the price goes down.”

“… while the supply and demand picture might capture a general fuzzy principle, it is far from being a law. For one thing, there is no such thing as a stable “demand” that we can measure independently –there are only transactions.”

“Also, the desire for a product is not independent of supply, or other factors, so it isn’t possible to think of supply and demand as two separate lines. Part of the attraction of luxury goods –or for that matter more basic things, such as housing –is exactly that their supply is limited. And when their price goes up, they are often perceived as more desirable, not less.” (emphasis added)

This example is relevant for banking systems (such as Australia) where residential mortgage lending dominates the balance sheets of the banks. Even more so given that public debate of the risk associated with housing seems often to be predicated on the economics 101 version of the laws of supply and demand.

The Power (and Danger) of Ideas

A recurring theme throughout the book is the ways in which economists and quants have borrowed ideas from physics without recognising the limitations of the analogies and assumptions they have relied on to do so. Wilmott and Orrell credit Sir Issac Newton as one of the inspirations behind Adam Smith’s idea of the “Invisible Hand” co-ordinating  the self interested actions of individuals for the good of society. When the quantum revolution saw physics embrace a probabilistic approach, economists followed.

I don’t think Wilmott and Orrell make this point directly but a recurring thought reading the book was the power of ideas to not just interpret the underlying reality but also to shape the way the economy and society develops not always for the better.

  • Economic laws that drive markets towards equilibrium as their natural state
  • The “invisible hand” operating in markets to reconcile individual self interest with optimal outcomes for society as a whole
  • The Efficient Market Hypothesis as an explanation for why markets are unpredictable

These ideas have widely influenced quantitative finance in a variety of domains and they all contribute useful insights; the key is to not lose sight of their zone of validity.

…. Finance … took exactly the wrong lesson from the quantum revolution. It held on to its Newtonian, mechanistic, symmetric picture of an intrinsically stable economy guided to equilibrium by Adam Smith’s invisible hand. But it adopted the probabilistic mathematics of stochastic calculus.” (emphasis added) Chapter 8

Where to from here?

It should be obvious by now that the authors are arguing that risk and reward cannot be reduced to hard numbers in the ways that physics has used similar principles and tools to generate practical insights into how the world works. Applying a bit of simple math in finance seems to open up the door to getting some control over an unpredictable world and, even better, to pursue optimisation strategies that allow the cognoscenti to optimise the balance between risk and reward. There is room for more complex math as well for those so inclined but the book sides with the increasingly widely held views that simple math is enough to get you into trouble and further complexity is best avoided if possible.

Wilmott and Orrell highlight mathematical biology in general and a book by Jim Murray on the topic as a source for better ways to approach many of the more difficult modelling challenges in finance and economics. They start by listing a series of phenomena in biological models that seem to be useful analogues for what happens in financial markets. They concede that a number of models used in mathematical biology that are almost all “toy” models. None of these models offer precise or determined outcomes but all can be used to explain what is happening in nature and offer insights into solutions for problems like disease control, epidemics, conservation etc.

The approach they advocate seems have a lot in common with the Agent Based Modelling approach that Andrew Haldane references (see his paper on “Tails of the Unexpected“) and that is the focus of Bookstabber’s book (“The End of Theory”).

In their words …

“Embrace the fact that the models are toy, and learn to work within any limitations.”

Focus more attention on measuring and managing resulting model risk, and less time on complicated new products.”

“… only by remaining both skeptical and agile can we learn. Keep your models simple, but remember they are just things you made up, and be ready to update them as new information comes in.”

I fear I have not done the book justice but I got a lot out of it and can recommend it highly.