Different goods are differently liquid

An evaporation in liquidity. September 13, 2012, at 12:25:27 to ~12:32 PM, eMini contract. From Nanex.

Steve Roth, who blogs at Asymptosis, recently posted a thoughtful critique of the idea of moneyness over at Cullen Roche's blog. (We've had a series of exchanges before on these questions). Even if my response can't sway Roth it should provide new readers of this blog with a rough overview of where I've been going with the idea of moneyness.

Let's start with definitions. Moneyness is a fancy word for liquidity. In short, it refers to the ease with which we expect to be able to trade something away for another item of value. Our expectations about liquidity are conditioned by an item's historical liquidity and modified by anything that we think could change it in the future, including new market mechanisms that might promote (or demote) that item's liquidity. All valuable goods & assets have varying levels of liquidity, or moneyness. Some will be easier to market when the need arises, others will require more effort.

Roth's first criticism, published on his blog last year, is that the

“moneyness” concept... seems to hinge on a single axis of “liquidity,” when in fact different units of exchange are differently liquid.

He goes on to give more detail at Roche's blog:

Suppose you have $10k in quarters. You can buy all the Snickers bars you want; there's a very liquid exchange market (quarters for snickers bars) out there. (Though need to tromp around to buy $10K worth of Snickers bars does seem to make it less “liquid”…)

But can you buy a car with those quarters? How about treasury bonds? No. Those quarters are completely illiquid relative to cars and treasury bonds.

Now think about treasury bonds. They're completely illiquid relative to both snickers bars and, but extremely liquid relative to fed bank deposits (reserve balances) — if you have 

I don't think I have to stretch this explanation out. Think about fed reserves/deposits — they’re (il)liquid relative to what other goods/assets?

So every financial asset — in fact every real good as well — has multiple liquidities, relative to every other asset/good.

I agree with Roth. Even the most liquid items are only tradeable along a few margins, or routes. The godfather of liquidity, a US dollar chequing deposit, can get you groceries or a car, but can't buy shares in IBM. A deposit at a brokerage can buy you IBM, but it can't get you a bag of groceries or a car. Roth's well turned phrase is worth repeating here, that different goods are "differently liquid", a point that I echo in Long Chains of Monetary Barter.

However, this doesn't mean that we can't arrive at a single combined measure for all of a good's different liquidities. All we need ask an individual is this:

"How much would I have to pay you in order for you to relinquish all rights to trade away your holdings of asset x for one year?" 

What we are extracting here is the individual's reservation price for x's liquidity. In this setup, the individual is allowed to continue to enjoy all the various pecuniary and non-pecuniary returns provided by x during a one year period, save for one return—its liquidity return. We are asking the individual to forgo each and every one of the good's multiple liquidities, or, put differently, the various margins along which x usually trades.

Whatever compensation the individual requires for giving up the right to trade away x along all routes is an indication of the foregone value that they ascribe to each of x's multiple liquidities. By dividing this price by x's total price, we can estimate what proportion of x's overall valuation our individual attributes to the liquidity component.

I think that this meets Roth's criticism, since in effect we are asking an individual to forgo each of an asset's multiple liquidities, all at once. We can go ahead and ask that individual the same question for each asset they own: how much would you have to be paid to forgo the combined multiple liquidities of a? and b? c? In the end, we'll have a list of all the individual's assets, along with the percentage contribution that each asset's liquidity provides to its total value. Having standardized our measurement of liquidity, we can now construct our individual's scale of moneyness for the coming year, ranked from least liquid to most liquid, the most liquid being that good who's liquidity contributes the largest chunk to its total value.

The upshot: the existence of multiple liquidities shouldn't prevent an individual from making private liquidity comparisons across different goods.

Which leads into Roth's next criticism, that estimates of liquidity differ across individuals. This presumably (Roth doesn't go into detail) hampers the effort to strip out a single measure of moneyness:

the liquidity of many assets depends on who you are. If you're a bank, your treasury bill is more liquid than if you're an individual, cause the bank can trade it for reserves and the individual can't. 

Again, I agree with Roth. Viewed from the eyes of a drug dealer, a chequing deposit is surely much less liquid than cash, while from the eyes of a typical nine-to-fiver, the opposite would be the case.

However, the charge of subjectivity shouldn't preclude us from extracting a market price for liquidity. After all, markets provide prices for diverse consumption goods like wheelchairs, which though an integral part of the life of an eighty-year old, from the perspective of a healthy twenty year old might be worthless. Milk is off-limits for the large portion of the population that is lactose intolerant while being popular with the rest—but markets are still capable of spitting out one price for milk. A particular good's liquidity, like a wheelchair or a carton of milk, is a consumption good the utility of which varies from individual to individual, yet in a competitive market these varying preferences should nevertheless interact together to create one market clearing price for these goods.

What follows is basic microeconomics. We can construct an individual's demand curve for x's liquidity by querying how much he or she would be willing to pay for those services at various prices. If we do this for all individuals and all assets, we can construct market demand curves for each asset's liquidity. Given a set of supply curves (supply is a totally different post), we can then submit this data to a Walrasian calculator to determine the market prices for these liquidities. These prices can be used to calculate the contribution made by liquidity to each asset's total market price, and from there we can proceed to construct the market's scale of moneyness, the asset with the most moneyness being that asset whose price is made up of the largest liquidity contribution.

The upshot is that the many differing personal scales of moneyness that Roth draws attention to can be reconciled by a market-wide moneyness scale. I hope that adequately answers Roth's points. One issue worth mentioning here is that we rarely get an opportunity to see living-breathing liquidity prices. As Nick Edmonds, who blogs here (and who should be on your reading list), points out:

I'm not sure that it is possible to extract out a market clearing price specifically for liquidity services, because it's assets that are traded not services. Each asset comes with a bundle of features yielding utility or disutility, not just the liquidity aspect.

Put differently, the difference between liquidity and a wheelchair is that liquidity doesn't stand alone as its own good but rather coexists as a service attached to an already produced good. Decomposing that service and its respective price from the rest is tricky.

Let me point out that fixed income markets do often provide accurate decompositions of the market price for liquidity. For instance, assume that FDIC-insured banks are offering chequing accounts yielding 0% and 1-year fixed term deposits yielding 2%. If we were to ask the market: "How much would I have to pay you in order for you to relinquish all rights to trade away your holdings of chequing accounts for one year?" ... the answer is 2%. So 2/100ths of the value of each chequing dollar is comprised of a 1-year liquidity return.

I've also spent some time trying to isolate the price of liquidity in equity markets, this post provides some detail.

But my best answer to Edmond's point is that this is a case of missing markets. We really don't have accurate prices for moneyness yet. One of the goals of this blog is to think about what these markets would look like, how you'd build them, and what they'd be useful for.