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Posts Tagged ‘monetary policy’

A Fiat Money Origin Story

April 3, 2016 13 comments

Nick Rowe has a recent post about Chartalism which got me thinking about the fundamental explanation for the value of money again.  He calls this an “origin story” and seems to be of the opinion that the origin doesn’t really matter, once it gets going you can remove the original source of fundamental value and it just stays up.  Kinda like Wile E. Coyote running off a cliff.  As long as nobody looks down, we’re fine.  I personally think this is nuts.  But I figure, why not try going through the explanation like an “origin story” from primitive commodity money to modern fiat money.  Maybe that will help?  I have mostly tried to avoid all of that because it seems unnecessarily confusing and I usually want to distill the story down to its most fundamental point as much as possible.  However, I think maybe this leaves people too much room to fall back on little misconceptions that are deeply lodged their thinking about this.  So why not start from the beginning and try to hammer out all the points (or most of them) in one try?  For the record, this is not a historical work.  It’s a made-up history that I think is fairly consistent with reality as it unfolded in the western world.  Whether or not the Chinese had some type of script that was linked to taxes thousands of years ago or there were some hunter-gatherers somewhere with a credit-based economy before commodity money became prevalent is not relevant to my point. Read more…

The Fisher Paradox

November 24, 2014 2 comments

There is a bit of a paradox underlying much of monetary economics. If real rates are independent of monetary factors, then a reduction in the nominal rate should be accompanied by a reduction in the expected rate of inflation (or vice-versa). Yet we typically observe, at least in the short run, that if the central bank lowers its interest rate target, it causes a higher rate of inflation. Of course, both old monetarists and market monetarists reconcile this by saying “never reason from a price change” (always good advice) and instead, reason from a change in the money supply (and expected future money supply), assuming sticky prices in the short run and then separate the effects on interest rates into the well-known liquidity, income and Fisher effects which allows for the real rate to change in the short run and for the nominal rate to go either way.

That’s all perfectly reasonable but lately there has been a school of thought emerging known as “neo Fisherites” who are bringing this issue back into the discussion. Nick Rowe (for one) has recently been taking them to task(here, here and here).

Now let me say for starters that I suspect everything Nick says about these papers is correct, and I’m not trying to defend them. I agree that denying that lowering rates raises inflation is contrary to all observations, and I suspect (though I haven’t read them yet) that his analysis of the specific papers as lacking in economic intuition and relying on strange assumptions to “rig” the results in favor of their prior beliefs is most likely spot on. That is how I feel about most modern economic papers I read, sadly. However, I think beneath the snow job and the tiny pebble of wrongness, there is actually a kernel of insight (or at least the pebble started out as a kernel before it got all mangled and turned to the dark side) and it is closely related to the stuff I have been trying to say. So I will try to flesh it out a little bit in a way that does not contradict everything we know about how monetary policy actually works.

Note that this actually began as a discussion of monetary and “fiscal” policy, which I intend to get to but I will put that off for a future post since just dealing with this Fisher paradox will be enough to fill a lengthy post by itself, but keep in mind that adding that piece in will be important for making this model look like the real world. (And also keep in mind that I don’t mean what other people mean when I say “fiscal policy.” Frankly, it’s almost tongue-in-cheek. All macro is monetary.) Read more…

It’s Demand for Money, Not Demand for Currency

August 12, 2014 5 comments

As regular readers know, I am a guy who sort of stumbled into monetary economics and as such, I have been going through a process of discovering the minutia of how everyone else thinks about money and trying to reconcile this with what I think I know. And it turns out that there are a lot of little issues that come up which make it hard for me to explain what I am thinking in the context of existing paradigms. These issues all basically revolve around the reason that money is valuable. I think this is because “money” represents the contractually obligated payment of debt. Most others seem to start from some kind of explanation that can basically be summed up as “it just is.”

The “it just is” explanation makes sense in the context of commodity money, since commodities have value independently of their use as money. However, I think this explanation is highly suspect when it comes to “fiat” money, which I would call “credit money.” Of course, historically, the line between the two is a bit blurred and this has largely, in my view, prevented the profession from drawing clear distinctions between them. Instead, we have basically just substituted base money in for the old commodity money and built our models around the assumption that this base money works essentially the same way except that we can make the quantity whatever we want.

This leads to a plethora of little assumptions that are difficult to flush out because, individually, they seem like they don’t matter. But they seem this way because they fit into a larger paradigm which is built on this (I think erroneous) belief about the reason money is valuable.

One such issue is the way we think about the demand for money. The simple version of the conventional wisdom goes something like this: There is a quantity of money in circulation. An individual can get rid of this only by spending it. The price of holding this money is the nominal interest rate. If people have more money than they desire to hold, they try to spend it. When everyone is trying to hold less money, either prices have to go up or interest rates have to fall until they are all holding the desired amount.

The problem with this is that people have another option (or options depending on how you look at it) which is to lend it or deposit it. However, the conventional wisdom has a nice way of dealing with this by conflating the two.

In the basic Macro 101 money multiplier model, we say that there is some amount of base money which gets multiplied by the banking system in the following way: People deposit some amount of it into banks who then lend it. The people who borrow it then spend it. The people who receive this money then deposit some of it into a bank and the process repeats until people and banks are holding their desired (or required) quantities of this base money.

In this process, the willingness of people to hold currency (base money) is crucial. The less currency they are willing to hold, the more they deposit at each iteration and the higher the money multiplier. This means that there is more spending which means higher “aggregate demand” and higher prices (and potentially higher output). This willingness to hold currency, naturally, depends on the rate of interest since this is the price paid for holding it rather than depositing it. People are assumed to pay this price because currency is more liquid. In the 101 treatment, it is typically (though implicitly) assumed that all spending is done with currency.

In this context, the banks are essentially reduced to an intermediary between borrowers and lenders. So when you deposit money, you are really lending it to someone else in order that they may spend it. So even though an individual may avoid either holding or spending the money, someone else has to end up holding or spending it and in aggregate all “money” (currency) gets either held or spent.

In this context, the interest rate can be thought to be determined endogenously as the rate at which the quantity of loans demanded is equal to the quantity supplied in the form of deposits, given the quantity of base money in circulation. Alternatively, we can think of the central bank setting (targeting) a given interest rate and providing the quantity of base money which is demanded at that rate (required to hit the target). In this context the distinction is seemingly unimportant.

In this model, anything which increases the money supply or decreases the demand for base money (including reducing the reserve ratio) increases “aggregate demand” and either prices or output or both.

However, this is not what I think the primary function of banks is. The primary function of banks is to create liquidity. This, I believe is true even in an entirely decentralized, free banking sector with a commodity standard. I have argued this before, so I won’t go through the whole spiel again here but I want to point out how this changes the way we look at money.

First of all, let us notice that it is the creation of a particular form of liquid asset (demand deposits) which separates banks from all other financial intermediaries. For instance, a bond fund acts as an intermediary between borrowers and lenders. However, a bond fund cannot create additional “money” the way a bank can. If you invest with a bond fund, you must take dollars (or whatever) out of your bank account, give them to the fund who can then give them to the borrower (buy bonds). The quantity of dollars in the system doesn’t change.

A bank, on the other hand, can take my deposit in a checking account, let’s say $100, and then lend it. When they do this, I still have $100 which I can spend at any time and somebody else now also has $100 that they can spend at any time. [Please note, that this is not an anti-fractional-reserve rant, I’m not saying this is bad, just that it is important. I’m working up to something much more subtle.] The reason you get a higher rate of return (normally) in a bond fund than in a checking account is that the checking account is more liquid.  In particular, it is worth noting that, like currency, a balance in your checking account is nominally denominated and represents a contractually (legally) acceptable form of payment of debts unlike shares in a bond fund or accounts receivable from a loan you made to your friend.  The latter must first be sold at some market rate to obtain some form of money (either cash or deposits) before a debt can be paid.

So whereas a bond fund makes a profit (which is to say “exists”) because it has (or is perceived to have) an advantage in determining profitable investments, the bank makes a profit because it is able to “borrow” at a lower rate (compared to a bond fund or other financial intermediary) because of its ability to offer a more liquid product in return which in turn is due to its ability to multiply a dollar into two dollars (and collectively into much more).

Now the subtle thing that I am working up to here is that it is not the willingness to hold currency that matters, it is the willingness to hold dollars in all forms (or insert unit of your choice). And this is where the “endogenous” vs. “exogenous” money debate starts to matter.

So the first thing to notice is that cash is not necessarily more liquid than demand deposits, they are differently liquid. There are some transactions for which cash is more convenient and there are some for which demand deposits are more convenient. In today’s world, it is probably the case that the latter make up the majority of transactions and even if they don’t, it is certainly not the case that cash is at all times preferred to deposit accounts and we only deposit money because it pays a higher interest rate. On the contrary, even if all transactions were slightly more convenient with cash, we would still hold most of our “money” in deposit accounts and withdraw it from time to time to make purchases because holding all of that cash would be inconvenient. So we can’t say that it is the interest rate which induces us to hold deposits instead of currency. It is actually liquidity preference. And indeed, until 2011, it was illegal to pay interest on demand deposits in the U.S. (and after that interest rates have essentially been zero anyway).

Now the thing we care about is neither the demand for currency nor the demand for money in a broader sense. What we are really interested in is aggregate demand. The question is which one of these, if either, helps us understand the behavior of aggregate demand.   Thinking about the demand for base money works fine for this purpose under two assumptions. The first is that the thing which is exogenous is the supply of base money. Second is that the process of multiplication, as outlined above, adheres to a stable process in all regards other than the demand for base money.

The first assumption is sort of wrong in the sense that it is not the way that monetary authorities say they conduct policy but taken alone, there is room to argue that this is not an important distinction which I and others have done. I think this does matter but only after we address the second assumption.

The second assumption holds much of the time but not always. It just so happens that it is when it breaks down that we run into problems. Specifically, it is the assumption that money which is deposited automatically gets loaned and money that is loaned automatically gets spent (therefore adding to aggregate demand) that is problematic. Assuming this allows us to draw a straight line from depositing currency to spending and keeps our “either spend it or hold it” paradigm intact.

However, if we look at this a different way, with “endogenous” money, things change. Instead of imagining that the central bank just dumps in a certain quantity of money and the system goes from there, imagine that they operate as “lender of last resort” to the banks and stand ready to supply whatever quantity of base money is demanded at a given rate. So the supply curve faced by banks will be perfectly elastic (horizontal) at that rate. Then the supply of loans will be perfectly elastic at some rate which accounts for the cost of running a bank and the risk of a given loan. This will then be independent of the willingness to hold currency.

Now if the rate on deposits is allowed to float freely, that rate will rise to the rate at which the central bank stands ready to lend reserves (the discount rate or federal funds rate). But if it is prohibited by law from being greater than zero, then it will be zero. This rate on deposits will affect the composition of people’s money holdings between currency and deposits but in neither case will that decision between currency and deposits ration the amount of loans made. If the quantity of deposits is less than the amount required to make the loans which are demanded at the discount rate, then the difference will be made up by borrowing from the central bank.

[Note that I consider normal open market operations, and not just lending at the discount window, equivalent to lending reserves to banks. This point is subtle but is a potential bone of contention and raises some other questions like how best to treat government borrowing in this context but I will leave this for later.]

In this context, we can see that it is the demand for loans which is important not the willingness to hold currency. If people are willing to borrow more at the rate set by the central bank, the money supply will expand and if they are not willing to borrow more, it will not, regardless of people’s preferences between holding cash and holding deposits. If people suddenly decide to hold more cash, the banks will simply borrow more from the central bank in order to make the demanded quantity of loans.

Now the central bank can still pump more money into the system by buying other assets and there will still be a type of hot-potato effect. But this is not driven by their willingness to hold currency, it is driven by their willingness to hold money and their willingness to hold debt. When they get the new money, they can either hold it (as either cash or deposits, it doesn’t matter which) or spend it on goods or they can reduce their debt. Either holding money (any kind of money) or paying down debt, increases their money to debt ratio. That is what matters. It doesn’t matter whether they hold it in the form of currency or deposits because depositing it doesn’t actually lead to more lending and then more spending.

At this point I started explaining how I think “unconventional” monetary injections work but it quickly became clear that that requires an entire post of its own so I will leave it for later. For now let me just stick to the point which I originally set out to make which is that it isn’t the willingness to hold currency relative to deposits that matters, it is the willingness to hold money (all money) relative to debt.

This point can be approached from another direction, if one is intent on taking the money supply as exogenous. It is clear that the thing the central bank wants to target is not the money supply but rather something like aggregate demand (some combination of prices and output or unemployment or something). It is obvious, I think, that if people suddenly decide to hold more currency and fewer deposits, the central bank will accommodate them by increasing the quantity of base money accordingly. In my way of looking at it this happens automatically as banks borrow more at the set interest rate but you may think of it as the central bank increasing the base through lending (which may include buying treasury securities) such that the interest rate stays the same. This would cause no change in aggregate demand.

In this case, it would be easy to do this because the increased demand for currency would increase the demand for base money. So it is hard to see how this would cause a problem if the central bank were not sticking to an arbitrary and counter-productive money-base target. Or, put another way, no demand for currency vs. deposits should cause the normal transmission mechanism to seize up. The important link in the money-multiplier chain is the willingness to borrow—the part which is typically taken for granted.

On the other hand, If people suddenly want to hold less debt and more money (any kind of money), then the central bank may not be able to pump more money in through that mechanism and increase aggregate demand, even at a zero rate. People may then start to wonder how easy it will be to get the dollars in the future to pay off their debts if the central bank’s injection mechanism is failing and they will try to get more money and less debt (and buy fewer goods) and it will spiral. The central bank will then have to find another way to inject money.

Similarly, in a state where there are large quantities of excess reserves in the banks and interest rates are near zero, if inflation expectations increased, it wouldn’t be the sudden unwillingness of people to hold currency and rush to deposit it into the banks that would lift aggregate demand, it would be the sudden willingness to borrow that would draw down reserves, increase the broad measure of money in circulation and lift aggregate demand.  It is this willingness to hold money (any kind of money) vs. willingness to hold debt that matters, not currency vs. deposits. However, this can only be seen once you notice that these two things (money and debt) are intimately related and free your mind from the shackles of the “it just is” theory of money value.

Is it Dedication to High or Low Inflation Which Leads to Communism?

July 31, 2014 3 comments

Nick Rowe has a post about the line between fiscal and monetary policy which largely reflects my sense of the matter which essentially is that the line is not very clear.  However, this part was the opposite of how I see it (sort of).

Too dedicated a pursuit of low inflation and the optimum quantity of money leads to communism, with government ownership of everything.

Also Scott Sumner echoed the same sentiment.  Since both of those guys are “at least as smart” as I am and have been at this a bit longer, this has got my wheels turning trying to reconcile their conclusion with my own and I think it raises several important points about the way I am thinking about this thing relative to them (and probably nearly everyone else).

First, I apparently don’t know what Sumner (and probably nearly everyone else) actually means when they say “fiscal policy” since I recently said something to the effect of: clearly a helicopter drop is monetary policy, but then in the comments, Sumner says this.

I’m strongly opposed to helicopter drops. I favor monetary stimulus when NGDP is too low. There is never any need for fiscal stimulus, even at the zero bound, and a helicopter drop is fiscal stimulus. It is wasteful and inefficient.

So I’m not sure where Scott’s line is.  To me, if the central bank printed money and dropped it from a helicopter, it would increase the supply of base money and this would be monetary policy.  Perhaps Scott is thinking that the government “borrows” from the central bank and then drops the money (or whatever they do with it), and so this increases the deficit and this makes it fiscal policy which may or may not then be offset by some monetary policy.  If that is the case, it is just a matter of who we are imagining doing the “dropping.”  To me this is splitting hairs, and not that important (which is basically the point of Nick’s post).   This post also deals with helicopter drops.

On a side note, I am not sure why Sumner objects on the grounds of inefficiency.  It can’t be a matter of changing the income distribution since he is such a bloody utilitarian after all.  This got me very puzzled so I went on his blog and looked for posts about helicopter drops and found this one which raises two possibilities for inefficiency.  One is based on the expectation that the government will someday raise taxes to pay off the money it dropped.  This also explains why it counts a fiscal policy.  The other is that it may cause peoples’ expectations about inflation to become unhinged and cause hyperinflation.

But that’s not really what I am interested in.  I’m not arguing for helicopter drops.  I’m trying to get at why we are at the ZLB in the first place and how monetary policy relates to the central bank ultimately owning stuff.  And I think this helps bring things into focus.

But if the Fed did accompany the drop with an explicit price level target, then the optimal helicopter drop would be less than zero.  Indeed if the Fed committed to say 4% inflation, the public would not want to hold even the current $2 trillion in base money (unless they were paid to do so with an interest on reserve program.)

That makes perfect sense.  If you hold the money supply constant, and increase expected inflation, people will want to hold fewer dollars at the current price level and so they will try to get rid of them by spending them which will drive up the price level.   Or at least this is how you would see it if you take the money supply as exogenous.

If you take nominal rates as exogenous, then an increase in inflation expectations, holding the nominal rate constant, will lower the real interest rate which will cause people to borrow more in order to buy stuff (both investment and consumption).  This drives up the price level and increases the money supply.  However, the interest rate regime can mimic the outcome in the money supply regime by raising the nominal rate to the point that the money supply doesn’t change.  Similarly, the money supply regime could expand the money supply until the nominal rate remained unchanged (or either of them could do something in between….or not in between for that matter).  That is not the important difference.

Either way you want to think about it, you have a tradeoff between the size of the money supply that is required to maintain a given price level and the expected rate of inflation.   If you are trying to hit a certain price level in the very short run, you can get there with a smaller money supply if people expect higher inflation in the longer run.  This seems to be the tradeoff between tight money and socialism that Nick and Scott have in mind and it is perfectly valid at any given point in time.  This instantaneous effect can be seen in my model as well (I’m pretty sure, although I can’t verify it right now due to technical difficulties…)

So essentially I have no argument with the way monetary policy functions in the short run.  My issue is about whether there is a stable long-run equilibrium.  This is where the relationship between money and debt becomes important.  If you think that money just floats around and has value solely because everyone believes that everyone else will always be willing to trade for it, then you imagine a demand for real money balances which depends only on the interest rate and output.  So if you can raise inflation, you can raise interest rates along with it and this will put you on a path where the desired money holdings will be smaller relative to the nominal value of output at all times.  Or in other words, the money supply will be higher but prices will be more higher and so the size of the central bank’s balance sheet in real terms will be smaller.

The point I am trying to make is that there is a sort of financial position that the economy gets into vis-a-vis the central bank when the central bank expands the money supply by expanding credit.  When they do this, they are essentially increasing the money supply by convincing people to lever up.  This can be done by either offering a lower nominal rate or convincing them that prices will be higher in the future.  Either one lowers the real rate of interest and makes it more attractive to go deeper into debt.  But this is not just more money floating around, it is more money and more debt which means that the public’s claim on the total money supply actually diminishes.

As an individual borrower, this works out fine as long as the central bank produces the anticipated inflation (0r more).  Then your income increases enough to repay the loans as expected and everybody wins.  But if everybody tried to repay their debts, the money supply would shrink which would mean that prices wouldn’t go up as anticipated.  So the central bank has to keep this from happening.  This means that they get into a pattern of perpetually lowering interest rates to further increase the money supply by increasing leverage and eroding the financial position of the overall economy.

Then one day they fail to produce the expected inflation, maybe because they hit the ZLB or maybe because they made a mistake, or maybe because people saw the ZLB coming and acted preemptively, or whatever and everything falls apart.  The reason it falls apart is because of the financial position of the economy.  It isn’t just that everyone suddenly thinks prices will only rise 1% instead of 2% so they start “hoarding” cash balances because the extra liquidity becames attractive at the lower inflation rate and this creates a death spiral (which is only “deathy” because prices can’t adjust fast enough to keep people from being laid off and output from falling).

It is that they think prices will only rise 1% instead of 2% and they took on a bunch of debt in anticipation of their income rising 2% which they now become concerned that they won’t be able to repay.  They start “hoarding cash” to repay the debts.  If they don’t, they will go bankrupt and lose real goods.  Since everyone else is in the same situation, everyone tries to grab the existing cash and pay off debts which causes the money supply to contract and prices to fall further until some combination of things restores the financial position of the economy to a point from which it can continue onward.

These things include:

1. Defaults.  This destroys debt without “destroying” money, which increases the ratio of money to debt.

2.  “Fiscal policy.”  This keeps the debt growing but it puts it on the government, so it can be done coercively (it doesn’t have to be individually rational).  This puts more money in circulation without increasing private debt.

3.  “Unconventional” monetary policy.  For instance a “monetary helicopter drop” by which I mean the central bank dropping money into the economy (a “fiscal helicopter drop” would then be when the government borrows money and drops it, in which case see number 2 above).  Or the central bank buying junk off of banks’ books for more than it is worth (this has some element of number 1 involved) or “adding zeroes” to their accounts, or buying up goods and services (rather than debt).  All of this will inject more money into the economy without increasing debt.  (We can throw dividends paid by the central bank into this category.)

So my point is that you can’t have what I would call a “long-run expansionary monetary policy” based purely on expanding credit.  You will need some combination of the above three things to keep the financial position of the economy on a sustainable path or to bring it back to such a path if it drifts away (as it is bound to do if you try to avoid those things for any extended period).

So in my model, it is not just about the willingness to hold cash balances, it is about the willingness to hold cash (or I would say “money” to include all balances denominated in dollars, or whatever) balances and the willingness to hold debt.  So to me the tradeoff between expansionary monetary policy and “socialism” is not just about how big the central bank’s balance sheet will have to be relative to the nominal value of output in a stable long-run equilibrium.  It is about how much of number 2 and 3 you would need relative to the value of output in a stable long-run equilibrium.  And I suspect that the more “expansionary” (the higher the intended rate of inflation), the more of this you will need in order to keep it from crashing.

Unfortunately, because of the previously mentioned technical difficulties, I  can’t show this in the context of the model at the moment.  But notice that there would be no such “socialism” necessary if there were no central bank in the first place and the money supply consisted of an exogenously determined quantity of some commodity like gold or silver.  In that case, there would almost certainly be some amount of deflation as the quantity of that commodity would most likely grow more slowly than output. (Or a better way of putting it: the rate of return on holding that commodity would have to be equal to the real rate of interest minus the liquidity premium and this would most likely be positive.  The selection of commodities which increase in quantity relatively slowly compared to output as money would happen endogenously.)

In this case, the private (excluding the central bank but not necessarily the government) claim on the money supply would always remain at 100%.  It is the adoption of a central bank which promises to create inflation by growing the money supply (by increasing credit/debt) which creates the gap between the money supply and the monetary wealth in the economy which has to be filled by some kind of non-credit injection of money or else closed by a wave of defaults.

Similarly, if the central bank just kept the rate of inflation (deflation) and the nominal interest rate equal to what they would be if it didn’t exist, it would do nothing, credit would not expand, the financial situation of the economy would not be eroded in any way and no “socialism” would be necessary.  It becomes necessary when they endeavor to expand the money supply by expanding credit.  The more inflation they want to create, the more they will have to do this and the more they will erode the financial condition of the economy in the absence of the three things mentioned above.  Or in other words, the more they will have to do those things to keep it going.  Or in still other words,  too dedicated a pursuit of high inflation and the optimal quantity of money leads to communism with the government owning everything.

Some Graphs

July 18, 2014 1 comment

In my last post, I put forth a model which leads to the crackpot conclusion that central banks, doing what they do, necessarily lead us into a “liquidity” trap unless there is some significant, and ever-increasing, leakage of money which is not backed by debt back into the economy (in other words “fiscal policy”).  I didn’t say very much about fiscal policy, there is a lot of work left to do which I intend to be doing for a while.  But at this point, just in case you are thinking that this theory is nutty, here are some graphs.

Quick history for the uninitiated.  The U.S. went off the (international) gold standard in 1971.  Then there was a decade of “stagflation” where inflation was high and, to put it (overly) simply, the Fed’s policy goals were not all that clear and people were still trying to figure out what was going on and what it meant in the long-run.  Then Paul Volcker was appointed chair of the Fed and vowed to rein in inflation which he did.  Since then, it has been supposed by many that the Fed has essentially been following a de facto inflation target.  The following graphs go from August 1979 (when Volcker was appointed) until the present.  We all know basically what output and the price level have done, so let’s cut to the chase.

Fed Funds Rate

fed funds rate

Ten-Year Yield

ten year yield

Now total debt is a little tricky.  Here is loans and leases in bank credit; all commercial banks, and the M2 money stock.

Loans and leases in bank credit, all commercial banks

 

m2

Notice that the ratio of M2 to total bank credit is about 1.74 in Nov. 1980 (this is as far back as the M2 series goes) and about 1.10 in Nov 2007.  Obviously, we know what happened next, and bank credit fell bringing the ratio back down to about 1.47 currently.  But of course, we also know what else happened….

“Fiscal Policy”

Federal debt held by fed banks

A Model of Endogenous Money

July 16, 2014 28 comments

I’ve been working on a macro model in which the quantity of money is endogenous and I want to post an early version of it here before I do any more complaining about other people not doing anything constructive.   I am attaching it as a pdf because I couldn’t get the equations to work in wordpress.  It is sort of a cross between a blog post and a working paper, lots of equations and boring math but with some very informal discussion here and there.  Also, to put all the math in would have been very tedious, so I tried to put in as little as possible, so some steps are omitted.  It should be possible to reconstruct what I did here from what I included but it would take some effort (and probably a mathematical computing package).  I think it is possible to organize it in a simpler way but I am still working on that.

The thing you should take away from this is that monetary policy, as we are currently doing it (inflation targeting) works much the way we think it works but that I think it either leads, in a predictable way, into a “liquidity trap” and a deflationary recession in the long run or it requires ever-expanding “fiscal policy” to keep this from happening.

A Model of Endogenous Money

 

 

Endogenous or Exogenous Money

June 15, 2014 27 comments

There are quite a few arguments in economics which are entirely superfluous.  One of them is over whether central banks determine the money supply or whether it is determined by the banking sector.  I have dealt with this previously (following along on the coat tails of Rowe and Sumner) but as I work through Keen’s lectures on “endogenous money” (see primarily 06 part 2 and 07 part 1) I can’t help but notice that this issue seems to be central to much of his criticisms of mainstream economics.  So in pursuit of my ultimate goal of rescuing the theory of money and debt from the Marxists–er, I mean “post Keynesians”–and folding it somehow neatly into regular old-fashioned economics, let me first address this whole endogenous/exogenous ball of wax.

The first problem with this debate is that it usually begins with a misunderstanding of the significance of those terms.  Endogenous and exogenous only have meaning in the context of a model.  A model can be designed in such a way that it treats something as exogenous, meaning that the determination of it is not explained in the model but taken for granted, or it can be designed in such a way that that thing is endogenous or determined in the model.  Neither one of these is right or wrong.  In the real world, everything is endogenous (except the laws of nature and some set of initial conditions).  Of course, if we are trying to demonstrate how or why a thing is what it is, we have to make a model in which it is endogenous or we are just saying what it is without adding any additional layers of logic to justify it.

Now keen characterizes the debate as over money being exogenous to “the economy.”  However, I think most staunch “exogenous money” types would still agree that the behavior of the central bank depends to some extent on conditions in the economy.  So, in some sense, as I said, everything is endogenous.  But let’s be honest, that is dancing around the issue.  The real question is what is the best way to model monetary policy.  It is hard to make a model where everything is endogenous.  And monetary policy, at least in theory, could be conducted independently of other conditions in the economy.  And furthermore, a large part of what we are usually trying to determine/demonstrate is the effect of monetary policy.  So it makes sense to treat this, somehow defined, as exogenous.  The question then becomes how to define it.

At this point, we arrive at the real crux of the matter.  The exogies claim that the central bank determines the quantity of base money and then the market determines the rate of interest.  The endogeroos insist that it is the other way around and the central bank merely determines the rate of interest and then the economy determines how much base money is needed and the central bank supplies it.  Now we have a report from the bank of England which tells us that what banks really do is the latter.  But the problem with Keen’s exposition on the subject is that he seems to act as though the rate of interest set by the central bank has no effect on the quantity of money which is thusly “endogenously” determined.

Essentially, this boils down to a common “paradox” in principles classes.  Does the monopolist take price for granted and choose a quantity or take quantity for granted and choose a price?  Answer: No.  The monopolist takes the demand curve for granted and chooses a price/quantity pair along that demand curve.  And so it is with the monetary authority, at least in the short run.  In the long run, there is a sort of supply and demand for money, though it is difficult to characterize them precisely.  The supply takes the form of some kind of reaction function by the central bank specifying either the quantity of money they will provide (if you are an exogie) or the short-term interest rate they will charge (if you are an endogeroo) under all possible economic scenarios.  The demand can be thought of as the quantity of money “the economy” will “demand” at any given interest rate (if you are an endogeroo) or the short-term interest rate that they will bid up to for any given quantity of money (if you are an exogie) under any given set of economic circumstances.  These two then interact in a very complicated way to determine the interest rate and the quantity at any given moment and market expectations of them at all points in the future which are represented by prices (including various interest rates).

Now, is the quantity or the price (interest rate) endogenous?  Answer: yes.  Better answer: they both are, of course, that’s supply and demand 101, can we get some harder questions in here?

So for most practical purposes, this distinction doesn’t matter.  It becomes the horizontal/vertical supply curve debate which Keen alluded to but I didn’t see him address (maybe he did it earlier).  That might make a difference for some minor reasons like the effect of misestimating demand or of changes in demand in the ultra-short run (faster than the CB can adjust policy) but as far as the big picture is concerned, this is a smokescreen.

But Keen seems to take it a step further than just arguing about what I would consider a bit of meaningless minutia.  He seems to be implying that monetary policy in general is not exogenous.  Which, in this context, since we know that the CB has the ability to determine monetary policy independently of what is happening in the economy, amounts to the statement: monetary policy is meaningless.  Here is the argument “in a nutshell.”  For the record, Keen is quoting Basil Moore.  By the end, the astute observer, thoroughly trained in sound “neoclassical” economics should see the flaw in this reasoning leaping off the page (or screen, as the case may be).

“Changes in wage and employment largely determine the demand for bank loans which, in turn determine the rate of growth of the money stock.

Central banks have no alternative but to accept this course of events, their only option being to vary the short-term rate of interest at which they supply liquidity to the banking system on demand.

Commercial banks are now in a position to supply whatever volume of credit to the economy that their borrowers demand.” (Moore 1:3-4)

In a nutshell

-The supply of money and credit is determined by the demand for money and credit.  There is no independent supply curve as in standard micro theory.

-All the state can do is affect the price of credit (the interest rate).

Did you spot it?  Here’s a hint: a monopolist doesn’t have a supply curve.  Does that mean the monopolist’s quantity is determined only by the demand curve?  No, because the monopolist can control the price.  But wait! says the smart kid in the front of the class.  If he doesn’t have a supply curve, and he is facing a given demand, and he controls the price, then isn’t he effectively choosing a quantity?  Like, couldn’t we just as easily say that he controls the quantity and the price is determined by the demand curve given that quantity?

Yes! Bonus points for the smart kid who doesn’t need them anyway!  Now all of the other people in the class hate your guts even more, congratulations!  A demand curve can’t determine a quantity all by itself.  There has to be something else determining which point along the demand curve we are at.  You can say that the central bank sets the price and then the demand curve, along with that price determine the quantity.  If you say that the CB sets the quantity and the demand curve, along with that quantity, determines the price, it’s not really different (assuming the demand curve is fixed and the CB knows what it is.  No doubt, Keen would say “well those assumptions aren’t true so your whole theory is garbage” but those are at best second order concerns).

Keen’s (and I guess Moore’s) mistake is to ignore the effect of controlling the price of money (interest rate) on the quantity demanded.  He acts as if this is a meaningless novelty.  But if the demand curve is downward sloping, this is everything.

Furthermore, the Keen/Moore theory has a gaping hole in the middle of it.  He claims that the money supply doesn’t “cause” price increases but that price increases cause an increase in the money supply.  But that leaves us with no way of determining a price level (or a change therein).  By the way, this is why it’s hard to make a model where everything is endogenous.  What determines all of them in that case?  Each exogenous variable you want to make endogenous requires another equation to identify it.  This presents problems if you are trying to have all of your equations make sense for some reason.  On the other hand, if you are just assigning arbitrary relationships between variables and calibrating them to fit the data, then no problem.

Finally, Keen begins with an empirical analysis by Kydland and Prescott which apparently finds evidence that changes in the money base lag the business cycle while changes in credit money (M1-M0) lead the cycle.  This is not surprising to me and fits with my view of the role of credit and monetary policy in the business cycle (which, for the record, I think has a lot of overlap with Keen’s view) but this does not prove that one causes the other.  The flaw is in Keen’s notion that if X follows Y, X couldn’t have caused Y (and therefore by implication, Y must have caused X).  Though he does make some equivocations for this, I think it shows what happens when you try to strip the “agent” out of economics, which seems to be Keen’s overarching mission.  You treat relationships between variables like the sterile cause/effect relationships that underlie most of the hard sciences.  The rate of acceleration due to gravity (near the earth’s surface) just is what it is and it is just a matter of measuring it.

In economics, things are seldom that straightforward.  Because you are modeling the behavior of thinking people, they have the ability to anticipate things that will happen in the future and this affects their actions today and in turn affects what happens in the future, just like those movies in the eighties with Michael J. Fox, it becomes a whole confusing mess with paradox on top of paradox that is difficult to sort out.  Or, to put it in the words of Scott Sumner quoting Paul Krugman: “it’s a simultaneous system.”