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A year-end market ritual two decades in the making: celebrated Wall Street seers promote their “forward looking” stock prices. But as you may know, this group (either individually or as a consensus average), we earlier this year proved to perform worse than a coin toss. Now they have again obliged us today, by misguiding investors and ordinary Americans with more random information that they claim emulates the future. Our prequel article, strategists: full of bull, was among of most popular blog articles ever (>1 million reads and a thousand shares) and went so far as being the cover and Most Popular story on Wall Street Journal’s MW, in addition to being written up in dozens of global news. We expect this sequel article to complement that (already featured in this Sunday’s New York Times print and Forbes), covering needed new math ground concerning what we learn here at the end of the year looking back is just as valuable as what we do at the start of the year looking forward. We also complete our 20th year of forecasts in our database that we make free for the public to explore; it is the largest such data set in the world. Last, we discuss the accuracy of this and any year’s forecast and the probability of these Wall Street strategists to have achieved their results by skill versus chance. This in turns aids in our understanding of how valuable such forecasts are for those who take the time to immerse themselves in it. Please read the prequel articles, as well at this sequel below. And you’ll discover the robust probability insight into exactly how unwise these celebrity seers truly are.
2017: a continuation of failure
We start by gratuitously fulfilling the wholly unnecessary curiosity of those who want to know what the 2017 market pundits are up to, released today by Barron’s.
Instead what we showed in the prequel article is that the Wall Street strategists tend to gyrate about this 9% typical forecast in the least helpful ways (e.g., stating +11% in 2008 when it was instead -49%). See forecasts in sky blue above, and the actual returns in pink. To be clear, and as we’ll show again below, it is far better to be within 10% of a -49% market year, then it is to be bulls-eye when the market happens to be a more normal +9%.
But because we see these wild gyrations in their forecast, and
over such a short period of time, this shows the Emperor was wearing no clothes,
at all. And we also notice something
disheartening or comical - depending on your perspective. The times they tend to make a judgement about
the relative change in the markets (outside their typical 9%), the market generally
then moves in the opposite direction,
and sometimes on bullish calls the market can instead drop significantly (we
noted the 2008 example earlier, but there are a handful of such examples).
Even though both years show -5% forecasts from a consensus
average perspective, the 2nd year is clearly the more accurate year for the typical strategists. The second issue is say we have a 3rd
year where the market crashes to -25%.
So while year 3 has a worse consensus error versus year 2,
the fact is it is far more important to have strategists who are closer when
the market moves violently, rather than be more close when the market barely budges
from its predicted value. This year is
reflective of what we typically see from strategists, who provided insincerely “safe”
bullish calls, which appear more correct on a consensus basis, but isn’t
necessarily tight nor useful for when markets eventually crash badly. Imagine the 4% and 15% strategists staying at
those levels in each of the 3 years above.
A year-end market ritual two decades in the making: celebrated Wall Street seers promote their “forward looking” stock prices. But as you may know, this group (either individually or as a consensus average), we earlier this year proved to perform worse than a coin toss. Now they have again obliged us today, by misguiding investors and ordinary Americans with more random information that they claim emulates the future. Our prequel article, strategists: full of bull, was among of most popular blog articles ever (>1 million reads and a thousand shares) and went so far as being the cover and Most Popular story on Wall Street Journal’s MW, in addition to being written up in dozens of global news. We expect this sequel article to complement that (already featured in this Sunday’s New York Times print and Forbes), covering needed new math ground concerning what we learn here at the end of the year looking back is just as valuable as what we do at the start of the year looking forward. We also complete our 20th year of forecasts in our database that we make free for the public to explore; it is the largest such data set in the world. Last, we discuss the accuracy of this and any year’s forecast and the probability of these Wall Street strategists to have achieved their results by skill versus chance. This in turns aids in our understanding of how valuable such forecasts are for those who take the time to immerse themselves in it. Please read the prequel articles, as well at this sequel below. And you’ll discover the robust probability insight into exactly how unwise these celebrity seers truly are.
2017: a continuation of failure
We start by gratuitously fulfilling the wholly unnecessary curiosity of those who want to know what the 2017 market pundits are up to, released today by Barron’s.
Forecaster
|
2017 target
|
% change from today’s
level
|
Stephen Auth, Federated
|
2350
|
4.0%
|
Jon Glionna, Barclays
|
2400
|
6.1%
|
Jeff Knight, Columbia
|
2450
|
8.2%
|
David Kostin, Goldman Sachs
|
2300
|
1.8%
|
Dubravko L-B, JPMorgan
|
2400
|
6.1%
|
Tobias Levkovich, Citi
|
2325
|
2.9%
|
Adam Parker, MS
|
2300
|
1.8%
|
John Praveen, Prudential
|
2575
|
13.1%
|
Heidi Richardson, BlackRock
|
2400
|
6.1%
|
Savita Subramanian, BofA ML
|
2300
|
1.8%
|
average (consensus)
|
N.M.
|
5.2%
|
From a probability and statistics perspective, it is not
interesting to explore the consensus
average price level (so shown as Not Meaningful in the table above), but rather
just the consensus % change. And of
course, on a continuous-geometric basis.
These predicted % changes shown in today’s Barron’s are likely a little
less than what the strategists’ originally envisaged, given the quick upward bounce
in prices, occurring in the background
as these forecasts were developed.
The other most
important thing anyway for you to see here is -that among only 10
strategists and despite the lower bias described from fast moving prices during
forecast formation- none of them
still hold a negative view for 2017! And
therein lies a prodigious irony, since
nearly 1/3 of the years -in the past two decades- have been negative (with
average return in those years of -18%). Think about that for a moment as you consider
the risk of the stock market. And that’s
more negative years than most people, including these self-described “investment
cognoscenti”, expect.
What’s troubling in relation to that is this in those same nearly
2 decades of forecast data, only 8% of individual
projections were negative. This
clearly shows how bullish-biased they are (as
if a typical 9% annual prediction versus a 4.5% actual return wasn’t enough!),
but the probability information given will still take this dismaying
performance to the higher level.
We should appreciate that an investor is likely to be less concerned about Wall Street
forecasters being conservative, as they will be concerned about being told that
the markets will simply rise double digits’ percent (and then instead be
treated to a decline of roughly that same amount!) And yes, that happens.
So we know there is some relevant asymmetry in what investors righteously care about. Even without asking for this explicitly, investors
are seeking to manage this frank risk with professional insights. Though no insights are to be found. As a case in point, in the 1/3 of all the years
coinciding to when the markets dropped, take a guess at how many of those years
did the consensus price estimate also show a drop?
A spectacular ZERO.
Demonstrating both no accuracy, and no value in the advice! And yes, you would always be better off
simply ignoring them, as you should ignore many unsolicited salespeople in your
life. Instead of the consensus, drilling
in on the individual forecasters’ records -during
those down years- we see that only 9% of those forecasts were
negative. So the equivalent rubbish as
the 8% overall negative forecast probability shown in the entire data set (not necessarily
conditional on just the 1/3 of years that happen to be negative)
Now imagine having a coin calibrated to show “above average” 2/3
of the time, and “below average” 1/3 of the time.
Flipping this coin would therefore outperform a Wall Street strategist! What’s worse is that simply guessing a positive
or a negative for a year is an arbitrarily meaningless, severity test. Sure it has some minor risk views we can
examine.
But what’s more interesting is to know that if we
parameterize this by simply looking at the actual correlation between the strategists’
predicted level and the actual level, that
relationship is negative! This distressing
result makes the variance in forecast error of 21%, which is improperly higher
than the raw market’s standard deviation of 19%!
The probability portrait we have here is very depraved, and actually
tends to get worse during the traumatic times when you actually require the
strategists to provide some insight (for example before a large market swing!) It would be bad enough if all strategists just
put out a constant 9% forecast each year, which of course is twice the annual return over the past 2
decades.
Instead what we showed in the prequel article is that the Wall Street strategists tend to gyrate about this 9% typical forecast in the least helpful ways (e.g., stating +11% in 2008 when it was instead -49%). See forecasts in sky blue above, and the actual returns in pink. To be clear, and as we’ll show again below, it is far better to be within 10% of a -49% market year, then it is to be bulls-eye when the market happens to be a more normal +9%.
Busted clock, true once daily
We all know that a “stopped” clock is right twice daily. What’s lesser known is that a clock, showing
a random time each minute, is also typically correct twice daily! In that sense only, both these clocks types
appear to offer the same value.
But the latter clock is actually a little worse than the former
clock, when we consider the uncertainty
in how much error there can be (between the clock’s result and the actual time). The first clock in this analogy is a perceived
“dumb” passive investor. And the second
clock here would be a speculating “monkey”.
And we’re about to see an important life lesson:
That it is
better to be smart while being perceived as dumb, than it is to be dumb while
being perceived to be smart.
Now mapping this random clock analogy to our investors, we
can think of the clock as being an unfair coin that results in “up” 2/3 of the
time and results in “down” 1/3 of the time.
On the other hand, the professional forecaster only predicts the market
results far less than half of this
(8% individually, and 0% on a consensus-basis.)
So these Wall Street soothsayers are the equivalent of a clock that is -by chance- only right once daily! This is appalling performance, and statistically
significant in being worse than a coin flip or a speculating monkey. Certainly
worse than a passive investor who can merely read the financial data, in an
unbiased way.
Of course these active scammers below don’t want to hear such
aggressive nonsense so they offer you this scripted rebuttal to justify their
fees: “we might not get the actual S&P price target right, but we offer clients
better value in getting the risk factors
right”. They confuse a confused and
fee-paying client, with their ability to add any value.
They cloak their terrible audited calls with other
smoke. Such as randomly pitching you on
the idea of large versus small companies, which industries, or which risk
factors. They’re playing roulette with
your money, their investment returns prove it, and The House wins all the time
by draining fees.
The defenses of Wall Street strategists are the equivalent of
stating one can’t offer you a great box of chocolates, but they can offer you
individual chocolates in a box, which are all great. Remember the market is a complete fusion of
all factors (such as all industries and company sizes), so it’s impossible to
know a subset’s relative performance well if you don’t know how it will perform
in relation to all the others.
And strategists collectively don’t know this either, if they
can’t in parallel get the overall market call right. See these smug zoots acting sage, but with just a
fantasy 9%, sitting between their
ears.
Now with over 20 years of forecasts (19 years of actual performance)
we are better able to judge the quality of the forecasters and apply a sense
for, probabilistically speaking, how
do they contrast with a “random clock”.
Using the following confidence interval formula estimate here, we can
see that the standard deviation of about the actual 1/3 market probability drop.
The formula works even if the markets
are randomly bouncing around each year, and strategist guesses don’t fall into up
or down portions so easily.
So when they project negative years only 8% of the time
instead of 1/3, they are demonstrating that they are greater than a standard
deviations worse than a monkey, or a coin-flipper,
or whatever mindless analogy one wants to use. While this alone shows that strategists have been
definitely offering skill in losing
money, as we’ll explore below, there is another similar math technique
covering this same point.
The Emperor hopes you forget…
… that you saw him wear no clothes. Wall street strategists happily talk about “price
targets” as though this concept has any value.
They falsely make the process appear scientific by providing a dash of “fundamental”
economic data to help substantiate their work.
But then they grotesquely gravy over this with a “price multiple” swag
that entirely invalidates any underlying reasoning. For this useless guess, that hope you’re
imprudent enough to pay them large sums of your hard-earned money to be told
simply what you want.
Let’s take 2016 for example, seeing the chart below. Once again we had the typical 9% forecast, and
the forecasts were relatively tight among strategists. And none of the 10 had a negative forecast
for 2016. But within just weeks of this year they were dumbfounded
by the deep market crash that happened as they were putting together their imaginary forecasts. No sooner did they return from their island
vacations, were they confused how to once again burned clients since they were
boxed in with their typical 2200 S&P forecast (the 10 forecasters ranged from
2100, to 2500). Yet the market fell below
1830 (or less than everyone’s 2016,
2015, and 2014 forecasts!)
In typical knee-jerk reaction, most of these strategists impulsively
just dropped their year-end “forecast” in early 2016, as shown as you follow
the red
line above. Sure enough though, when the
market then rebounded and advanced through the summer, most of them again were
disbelieving it and revised this same year-end “forecast” again (this time up by
just less than 40 points, to 2138). The
market is currently at 2258; 5% higher
than their most recent call of 2138 (or 3% higher than the original 2200
call). Even the very reasons they gave for
being concerned in 2016 turned out to be false: no one mentioned the January
crash, nor Brexit, and they certainly
got every aspect of Donald Trump wrong.
Someone needs to give the Editor at Barron’s a lecture that
the term “forecast” starts with the prefix “fore”, suggesting something in advance. This should not be turned into a courteous second-guessing
backcast, which means look at the random stock pattern and state that you
brilliantly knew this would happen with your money. As a reminder these cumulative changes over
time can be quite alarming, and of course generally uselessly bullish even to the most timorous marketers (as shown
here through 2015).
Strategists are the vilest types of fortune tellers, since
they completely miss the necessary downturns in the market, which can wipe out years of your hard-earned
savings. And that’s what some experienced
so easily, earlier this year.
During such downturns we see in the chart above that they
also didn’t advise clients to stay the course, since they themselves dropped
their forecast and led people to believe the markets would then only return a
lower 8% return (projected in late February), when it would instead rise 15% since
then. A couple mathematical issues make
Wall Street forecasts terrible, as we can so finely see this year. In addition to the actual difference between
the predicted level and the actual level (this is the focus of many simple
critiques on strategists).
The couple ideas here are that there is still wild dispersion
in the analyst outcomes such that even if the consensus is correct, the larger
dispersion in forecasts are less attractive in judging the analysts’ accuracy. And their
actual dispersion has zero relationship to anything meaningful. For example, say we have two back-to-back
years where the market returned 4%:
Year
|
Strategist 1
|
Strategist 2
|
Consensus error
|
Dispersion of error
|
1
|
4%
|
14%
|
-5%
|
5%
|
2
|
9%
|
9%
|
-5%
|
0%
|
Year
|
Strategist 1
|
Strategist 2
|
Consensus error
|
Dispersion of error
|
1
|
4%
|
14%
|
-5%
|
5%
|
2
|
9%
|
9%
|
-5%
|
0%
|
3
|
-15%
|
-15%
|
-10%
|
0%
|
Using this discussion, we should note that none of the
strategists rise to the level of providing value, skilled or luck based, though
some are quite skilled at detracting value.
Take the Bears Stearns’ strategist whose terrifying forecast accuracy is shown below and
are the epitome of the revolting surprises that await investors who use Wall
Street “insight”.
For the overall industry of strategists, see this chart below
that shows how each year’s market returns contrasted against that year’s
consensus forecast. And the size of the data shows the
dispersion in errors (also colored red for large and blue for small).
What we see from this is that 2016 (in dark green) was an ok year
relative to the original (2200 S&P) forecasts Wall Street firms put out 1
year ago. Though one can see in the red composite
that this year was already a typical consensus forecast year of about 9%. And of course -in typical depressing fashion-
these forecasters then lowered those
estimates at the wrong time and in a sense shot themselves in the foot
again. These are lessons you should only
be reading about in a web log, and not experience with your nest egg.
Be careful in 2017.
With reduced yet positive Wall Street forecasts, you might neglect the
exceptional false sense of accuracy that comes with it, particularly this year
as the bull rally has extended without a meaningful pullback in some time. Implying room for unusually great uncertainty,
in the early part of the year.
> Now imagine having a coin calibrated to show “positive” 2/3 of the time, and “negative” 1/3 of the time. Flipping this coin would therefore outperform a Wall Street strategist!
ReplyDeleteWhat do you mean by "outperform"? If the market is up 2/3 of the time, the consensus forecast (always up) will be right with probability 0.6667. You coin will be right with probability 0.5556 = (1/3)*(1/3)+(2/3)*(2/3)
So to help clear up any issues with the concept of a coin flipping analogy, most of which are arising from some using an unsophisticated vantage point to think all the way through the logic. The “coin” is not merely a coin calibrated at a return of 0 and only the probabilities altered. Advanced students of probability theory and finance can appreciate that it must be one calibrated to mimic the effect of the returns being “above typical” versus “below typical” for a year.
DeleteAnd as well, the resulting performance metric can be extended beyond a simple frequentist measure, but as we discuss in depth in this article (and surely throughout the blog) must include the very real risk concept of “what would have happened” if you invested capital (more or less) based on the strategists' view (versus that from your coin flip)!
Just to be clear, I agree with your main point of forecasts being mostly useless. But I don't see how they are worse than the coin (which is even more useless). Feel free to delete the coments once again, I won't insist.
Delete