How to reduce your risk?

Let’s do an experiment.

I am going to present with you with an investment decision with two options.
Please choose the one which will reduce your risk.

You have £100k.

A. You can invest your money by buying a 10-year bond with a 10% yield

This means you will receive £10k per year and your £100k back at the end.

B. You can put your money in a bank checking account which currently pays 10% APR

This means that if interest rates stayed at 10% then you again receive a total of £10k every year with your £100k initial capital still yours.

These investment options look identical if interest rates never change.  But the rate of interest is not going to stay at 10%.  To make it very clear I will let you know that interest rate are going to change tomorrow and will either be 5% or 15% but you do not know which.

Remember I’m asking for the option which reduces your risk.

Answer in a later post.

Models

Since I discussed models in my last post, I could not resist saying something quickly about what they are for. This is a very important topic and one I will frequently return to.

But for now, I will just give you a brilliant short story from the most inventive and thought-provoking author I know.

Jorge Luis Borges. “On Exactitude in Science” or “Del rigor en la ciencia”.

Can you put a price on the environment?

I am an economist by training, experience and by inclination so the answer seems an obvious yes. Welfare economics generally looks at exactly these sorts of questions. However, the debate and current policy mix for Climate Change does not appear how I would expect it to, especially given the lack of agreement on carbon pricing which has dropped out of the discussion.


Assigning monetary value?

A common mistake that economists make is, because a given model works for some aspects of human behaviour, they assume it can always be used and possibly generalised to all human behaviours, often by adding some sort of arbitrary assumption to make it fit. The consensus in neoclassical modelling is for a marginalist approach with rational agents.

Take gift giving, it is economically inefficient but still takes place. The neoclassical approach is to assume that cash giving has an unexplained stigma or that buying your lover a thoughtful gift acts as signal that you love them. Of course, these fail to resonate with our actual experience of gift giving and receiving, and so fail the common-sense approach.

This is a classic logic error – there are many (infinite?) ways to model and explain behaviour. Just because you have one that you like does not mean it is the only one or that it must be superior to the others. If to make your model fit the external reality you are required to add counterintuitive assumptions then this can often sign to rethink your entire approach.


What other approaches are there?

The environment is a moral not an economic question

This idea was sparked reading Michael Sandel’s “What Money Can’t Buy”.
As a political philosopher, he is highly critical of the current trend towards adding commercial thinking and monetary values into our lives, using moral arguments of unfairness and degradation of values. There are many examples: paying to avoid queuing, the rise of corporate boxes at venues, paying to get a nicer prison cell and, in this category, he also places the environment.

Another famous example of a counterproductive effect of replacing a moral code with a monetary incentive is a school adding a fee for late pick-up of children after school. Parents were much happier paying a price for lateness than infringe a moral obligation to pick up the children on time and the incidence increased. Related to this, when people are paid for blood donations, the amounts and quality of blood donated both fall.

When Sandel in 1997 wrote a piece in the New York Times arguing against carbon trading, he was inundated with “scathing letters – mostly from economists” who assumed that he simply did not understand that their model, that trading would always be good, was obviously true. 20 years later some economists may be more sympathetic to the idea that not everything should be analysed in this way. http://www.nytimes.com/2011/04/22/opinion/22krugman.html?_r=1&hp

A different view?

Do the efforts to “stigmatize” excessive carbon usage and “promoting virtuous attitudes” work? Moral codes in society are very powerful. But as a prevention mechanism, they do not always work. They may not be as universally shared as their advocates like to assume; If you want to reduce teen pregnancy the approach of teaching that sex before marriage is immoral and the promotion of abstinence have been shown to be highly ineffective. The attempt to change people’s behaviour on carbon consumption by stigmatizing it appears to me to have the same flaw. People may feel a little guilty but will not actually change their behaviour, whilst the moralisers can enjoy the feeling of superiority, getting us nowhere.

I was once memorably informed that my willingness to experiment with models and analysis that put a monetary value on human life was “sociopathic”. I did wonder at the time if they knew or cared how counterproductive it is to alienate sympathetic non-believers if your objective is to influence behaviour.


Lexicographic vs marginal preferences

Amartya Sen is a wonderful writer on justice, development and social choice who developed ideas in welfare economics beyond thinking purely about Pareto optimality. I was recently reminded of this concept in Marc Lavoie’s “Introduction to Post-Keynesian Economics”. It was striking to me that I had forgotten about it which implies it is not commonly used.

Faced with needs, the idea is that people do not make marginal decisions across every item but rather make choices only within categories. There is a hierarchy of needs, and only when the essential ones are obtained, then the next category can be bought. Therefore, substitution of goods only happens within categories and not between them.

For the environment, people that think that climate change is a compelling moral issue then discussing the price is bizarre and inappropriate. It is a moral need and comes in a very important category. For people who have consumption desires they find more pressing such as housing, clothing and food, then the morality of climate change is in a lower category and so not highly valued. This helps explain the observation that when asked how much they value the environment people’s answers tend to be extremely high numbers or extremely low ones. There is no smooth substitution along an indifference curve. It also explains why people express that they care enormously about the environment when the economy is doing well and it is not mentioned during a recession.

This sort of heterodox critique of neoclassical marginalism is compelling, but the next step of suggesting a policy is lacking. Lavoie says that “post-Keynesians have never really developed their views on consumer choice in any systematic way” and only have “insights”.

Where next?

I am left thinking that at pure moral non-market approach to dealing with Climate Change is not effective. A lexicographic approach gives a useful description that fits observed behaviour but does not give me any useful approaches to designing policy. So, I return to welfare economics and thinking in terms of cost-benefit analysis and externalities.

Framework for valuing equities Part I- Compared to bonds

A useful framework for considering one investment is to compare it with another, you can then do analysis to decide if you prefer one to the other. This is of course relative value and if the benchmark asset is government debt, this is a solid place to start.

The “Fed Model”

The “Fed Model” is that the stock market yield is related to the yield on long-term government bonds. Like so many models, it has fallen into disrepute seems to come more from its misuse over the years as opposed to its intrinsic failings.

Expected Returns for Equities and Bonds

A way to start thinking about this model is to start with the expected returns on the two investments, equities and bonds. Consideration of the spread of returns and the distribution around the expected return can come later.


Bonds

Expected return for US government bonds in nominal terms is as easy as it gets – yield to maturity.
I will ignore the remote possibility of a default on the debt.

Equities
Expected returns for equities is harder; there is a choice of possible yields, with none necessarily equating to the eventual return.

  • Dividend yield
    Problematic given that dividend policy is a management decision. Microsoft’s decision not to issue dividends was not a good indicator of its total return.
  • Earnings yield
    More sensible i.e. E/P (or just PE ratio inverted).
  • Earnings yield + Inflation

Considering we are using historical earnings, to get a future value we could add an inflation component given that earnings would be expected to rise along with inflation, in the long run.

Testing the expected returns model for Equities

Back-testing expected returns to 10 year actual returns, the US equity market shows surprisingly good results, especially post WW2. This makes intuitive sense as one would expect that buying equities with a lower PE or when inflation is higher would produce better returns. But the strength of the relationship is eye-catching, implying that current earnings do on average provide a good guide to expected equity total returns.

If you come from a purely “efficient markets” view of the world, this may seem blindingly obvious with equity value as simply the present value of the earnings stream. But bear in mind that earnings yield (E/P) is not a yield in the same way that bonds have a yield, unless you make an argument where the word “assume” occurs very frequently.


Expected Returns for Equities versus Bonds

Given that we are happy with our model of expected returns for both equities and bonds, we can move on to comparing one versus the other.

The model for expected return of equities over bonds would look like

We can use data from end 2016 to get actual numbers

This difference/expected return is often called an equity risk premium (ERP).

We can now back-test its use in predicting if the equity market will actually outperform the bond market. Chart below again shows pretty decent relationship – but can we say how good?

expected vs actual

Given the nature of the data we should not perform a regression, and instead here is a truth table for the data back to 1950.

With ex ante premium (i.e. model) above 2%, then equities outperform bonds 93% of the time.
With it below 2%, then equities only outperform 37% of the time. That is a pretty solid result.

Summary

This investigation that equities look cheaper than bonds. If this is the only model you use then the clear imperative is to buy equities now. Before I make my mind up, I want to think about fixed income valuation next.