Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

In this Discussion

Here's a statement of the obvious: The opinions expressed here are those of the participants, not those of the Mutual Fund Observer. We cannot vouch for the accuracy or appropriateness of any of it, though we do encourage civility and good humor.

    Support MFO

  • Donate through PayPal

The Reliability of Expert Forecasting

Hi Guys,

Often, our individual investing decisions are nudged in one direction or another by an expert’s forecast. How credible, how reliable is the expert prediction record?

That is not an easy question to answer. Typically, experts are more focused on satisfying their base supporters and/or being controversial enough to gather media attention. They rarely advertise their record, their batting average. I suspect they don’t even keep score.

As investors, since we are influenced by market guru opinions, we should seek that score. CXO Advisory Group did yeomen work by doing so for many years. Unfortunately, CXO has discontinued that useful service. Here is the CXO Link to their final report:

https://www.cxoadvisory.com/gurus/

Note the disappointing bottom-line statistic. About 68 experts were evaluated. Over the entire testing period their cumulative winners score was a little below a coin toss; the famous dart tossing monkey would have won that competition. The much condemned Ken Fisher ranked second highest with a 66.4% accuracy rating.

An even more serious and more rigorous examination of expert’s reliability is a long-term prediction tournament organized by University of Pennsylvania Professor Phil Tetlock and co-leaders. It is funded by the Intelligence Advanced Research Projects Agency (IARPA).

This project has been ongoing for several years now, and it is uncovering some positive findings. Not surprisingly, some individual guys are persistently more successful than others. When these wizards are assembled into teams, their correct scores improve and persist over time. To a limited extent, with special training, scores can be improved.

Consistent with Tetlock’s earlier book, individuals who are classified as Foxes have superior forecasting records over those classified as Hedgehogs. A Fox is flexible and has knowledge in many diverse areas whereas a Hedgehog masters a single subject.

Age and social status does not automatically translate into outstanding prediction success. This finding could surely upset the current social structure. It turns out that superstar world event forecasters like Paul Krugman and Thomas Friedman do no better than well informed college students in many instances. Here is a Link to an Economist article that summarizes a few of the intermediate IARPA study findings:

http://www.economist.com/news/21589145-how-sort-best-rest-whos-good-forecasts

Here is a Link to a recent update of the projects status and followed by a Link to a 50 minute video interview with Phil Tetlock:

https://goodjudgmentproject.com/blog/?p=187

http://edge.org/conversation/how-to-win-at-forecasting

When making investment decisions we sometimes defer to the wisdom of these experts. The scientific evidence suggests that this trust might be misguided. The cautionary takeaway here is that we frequently give too much credibility to these experts. Experts are not God and are fallible. They could be harmful to wealth accumulation, so do independent research.

Loads of studies reinforce these current IARPA findings. To illustrate, I’ll summarize a few shocking observations related to the medical community. In reading lab tests, the experienced technician who completes the test does better at interpreting the results than does an experienced nurse who does better than the requesting physician. When challenged again at a later time, the same doctor will change his evaluation a statistically disturbing number of times. Patient beware.

I cite this specific example because on Monday, and two weeks later, I’ll be having cataract surgery performed to both eyes. It’s an established and reliable procedure so I’m highly optimistic anticipating the outcomes. My wife successfully went through the same surgery with the same doctor a year ago. She observed just how useful the doctor’s assistant was and how much this doctor trusted, complimented, and relied on her assistant, of obviously lower status within the operating room. That trust and teamwork can only work to improve all outcomes.

Teamwork and team decisions formed from members with a diverse background, different experiences, and independent preferences integrate effectively to make better informed decisions with higher likelihoods of positive returns.

I’m a relatively inactive market player who uses pedestrian investment practices endorsed by a huge body of academic elites (like Harry Markowitz, Bill Sharpe, Gene Fama, Ken French, and Burton Malkiel), a larger body of institutional and industry superstars (like John Bogle, Larry Swedroe, David Swensen, and Richard Ferri), and a respectable number of senior financial writers (like Jason Zweig, Bill Bernstein, Scott Burns, and Jonathan Clements).

I’m comfortable joining this team of high scoring and diverse group of investment experts. These independent guys are all proponents for a low cost, low turnover, long time horizon, relatively inactive investment philosophy. Rather than doing something, they tend to advocate just sitting quietly. They prefer to allow compounding to work its magic.

Although I’m a very conservative investor, I do learn from the many fine posts and information dense references quoted by MFO participants who adhere to a far more active strategy. There are many navigable courses across a sometimes unfriendly and stormy sea.

Best Regards.

Comments

  • MJG: Wishing you the best of luck on your cataract surgery. My wife, with vision in only one eye, went through this a year or so ago on that one working eye. She came through in fine shape, to our great relief. I hope for the same results in your case.

    With respect to your observations on teamwork, I'm in complete agreement. The most interesting and productive experiences that I had as a radio technician for SF certainly involved challenges utilizing the different skill sets of my fellow technicians.

    Sincerely- OJ
  • Also wish you luck on the surgery. In my experience (involving others) it's always been a very helpful procedure.

    Many years ago I recall a study on predicting interest rates. It showed that simply assuming that what had happened last year was going to happen again next year provided significantly more accuracy than the predictions of Wall Street experts. I've never seen anything to make me doubt the natural inference from that.
  • edited April 2014
    1. The first part is conflating a number of different types of experts: from macro economic on which there is no actionable conclusion to investment news letter writers which anybody can be. Is it surprising that over such a wide and diverse group, that it is difficult to arrive at a consistent criterion for success let alone any conclusion on who to follow or not? What investment decision does anyone make based on Friedman or Krugman?

    2. The only experts I consider for my investment activity are people who are practicing it i.e., fund managers whose performance is quantifiable and measurable. If you compare this universe to the other group mentioned here, doesn't this just boil down to the same active vs passive debate?

    I am just amazed at the number of word-processed ways this debate and the same conclusions keep cropping up.
  • All the best MJG on your upcoming cataract surgery.
  • Ditto on the good wishes for your surgery.
  • Hi cman,

    Thank you for your brief commentary.

    You asked if Krugman and/or Friedman had a market impact. You wondered if all these posting devolve into a passive/active debate.

    I believe that both referenced journalists do influence investor decisions, at least those of their large fan base. They are very popular from both their book and journalistic platforms, and have established loyal followings who do and will translate their economic and international views into actionable investments.

    Paul Krugman is a Nobel recipient economist. When he talks, folks listen and react. I’m specifically thinking about the recent firestorm that he initiated with his Bitcoin denunciation. Investors definitely take action when his US economic perspectives are published.

    Thomas Friedman consistently talks the talk of how globalization impacts the world’s power structure. An investor who completely ignores his changing world observations and predictions risk misgauging the International marketplace.

    Both these gentleman have the capability to at least move the markets a little. However, I especially named them in my post because they were explicitly mentioned in the various Professor Phil Tetlock stuff that I referenced.

    I completely agree that it does “just boil down to the same active vs. passive debate” given that “the only experts I consider for my investment activity are people who are practicing it”. That’s a very limited field.

    If the fund managers have any integrity whatsoever, surely the passive fund managers are devoted to Index products and the active fund managers are equally committed to an active approach. That’s obvious enough. Employment forces these folks to be very rigid. In that sense, their world is simple and very stable.

    That’s why I like expanding the opinion universe to academia, to institutional gurus, to market pundits, to financial writers, and to MFO contributors. Each cohort brings a different perspective to the investment decision table. And within these cohorts there are passive and active defections. Things change and so do investing judgments.

    Thanks again for participating.

    Best Wishes.
  • MJG said:


    I believe that both referenced journalists do influence investor decisions, at least those of their large fan base. They are very popular from both their book and journalistic platforms, and have established loyal followings who do and will translate their economic and international views into actionable investments.

    Paul Krugman is a Nobel recipient economist. When he talks, folks listen and react. I’m specifically thinking about the recent firestorm that he initiated with his Bitcoin denunciation. Investors definitely take action when his US economic perspectives are published.

    Thomas Friedman consistently talks the talk of how globalization impacts the world’s power structure. An investor who completely ignores his changing world observations and predictions risk misgauging the International marketplace.

    Both these gentleman have the capability to at least move the markets a little.

    Isn't all of this alleged effect on the markets, just opinion unsupported by rigorous documentation, studies and proofs that you blindly crusade for and ask from others when you don't agree with it?:-) It may just turn out to be a strawman to shoot down too. Not suggesting you would necessarily stoop to that level.

    But seriously, just about everything moves markets. Without evidence to that contrary, does anyone believe that any of these guys move market in any way that makes the slightest bit of difference? The Farmer's Almanac probably moves markets more than any of these guys but still you wouldn't consider the efficacy of that almanac to judge whether you should be active or passive in investing.

    I completely agree that it does “just boil down to the same active vs. passive debate” given that “the only experts I consider for my investment activity are people who are practicing it”. That’s a very limited field.
    But that is also the only relevant and meaningful field for comparison between the two groups. Because both are dealing with and describing investment theses in comparable ways (domain and level of abstraction).

    Surely, you are not suggesting that it is suitable to compare apples and oranges because the domain of apples is more limited than all fruits (and some fruitcakes in this case)?

    That’s why I like expanding the opinion universe to academia, to institutional gurus, to market pundits, to financial writers, and to MFO contributors. Each cohort brings a different perspective to the investment decision table. And within these cohorts there are passive and active defections. Things change and so do investing judgments.
    Sure, you can get weather forecasters into the equation too if you wish. All true in general.

    It is when conclusions are drawn from such a universe that the relevance and use of such opinions and the logic of that inference needs to be considered valid or not. And this is assuming that such a consideration adds to clarity than intentional hubris.

    I don't invest in index funds (or active funds) because Friedman couldn't make reliable macro economic forecasts even if he was trying to do so. Seems like there are far more direct reasons to do so for both index and active funds.
  • Hi cman,

    Boy, you’re quick. Perhaps that’s why you missed some elements of my post that pre-answer your questions.

    It is certainly true that I can not reference a study that quantifies the statistical impact that either Krugman or Friedman have on market pricing. I doubt such studies exist. But I did specifically reference the Bitcoin tempest that Krugman helped fire.

    Both of these guys are successful career writers with worldwide exposure. They have a wide reach. I opened my dialogue with the statement “I believe”. Don’t you believe they have an investment impact? If these guys don’t impact the market, no writer does.

    Writing has long been the historical media to energize action. Don’t you believe you influence some investment decisions here on the MFO site? I believe you do even if modesty prevents you from taking credit.

    Relative to forming an investment advisory group, I agree that I would not likely select a weatherman nor a truck-driver. The team benefits from diversity, but only from informed and relevant diversity.

    Wait, I’ve entertained second thoughts on this matter. If I had a Commodities component to my portfolio, I might well add both a weatherman and a truck-driver to my investment council. I recognize it’s a stretch, but that’s inline with many of your logic arguments.

    I consider these types of exchanges as a waste of time since they really do not add value.

    Best Wishes.
  • Hi Guys,

    Thank you all for your kind well wishes. I really expect to be seeing the world more clearly in the near future.
  • There are studies that show a general increase in the occurrence of cataracts in humans due to increased solar activity. One good investment would be a pair of quality sunglasses. Investing in our own well being is always positive.
  • And you have completely missed the logical flaw pointed out it seems.
    MJG said:


    Don’t you believe they have an investment impact? If these guys don’t impact the market, no writer does.

    Did you miss where I said almost everything that is about the market affects the market if you don't care to what extent and whether it makes any difference? How do you get the above questions from that?

    The logic of your post is that there are a lot of experts out there and they don't have a good record forecasting. So following them is folly, so it is better to follow the other group who preach passive investing.

    The flaws in that argument consist of

    1. non sequitur - the premise that experts are wrong in various fields doesn't imply the validity of other people who preach passive investing.

    2. False choice. All of them can be wrong.

    3. Nirvana fallacy - Perfection in forecasting isn't necessary to gain so unless you show a negative net effect of following of such experts which is difficult to quantify since that influence whatever it is, is at best diffuse.

    I consider these types of exchanges as a waste of time since they really do not add value.
    I find endless repeated proselytizing of an ideology especially with flawed logic, tedious and at best useless and at worst misleading.

    But that is why we have a discussion group. To air opinions. The value is for the reader to judge of course, since neither of us are objective in that direction of our own writings.:-)
  • I only signed in to mention my favorite Bernstein comment (perhaps slightly misquoted): "The only reason the term "guru" is used so often is that it's so much easier to spell than 'charlatan.'"
  • Very funny. BTW, which Bernstein? Three well known financial writers: Peter; Richard; William
  • Cataract, like most, is not a sure thing surgery. I had one that required another follow up retina surgery. As it turned out, there was no improvement from before the original surgery but it no worse than it was before. A year later, my second eye went fine, with another Dr. No great explanation, happens in maybe 5%.
  • Hi Ron,

    Yes indeed, every surgical procedure has a risk element. There are few 100% guarantees when doing much of anything.

    I am very sorry to learn of your outcomes. One out of two plus procedures is a disappointment. You seem to have adjusted and accepted the initial setback with a positive attitude. Good for you.

    The odds that you cited are similar to those quoted to me by my surgeon earlier this week. She has about 12 years of operating experience and I’m confident in her skills.

    She suggested a 97% likelihood of success for each eye, a 1% chance of the need for a redo, a 2% probability of no change whatsoever, and a miniscule odds of blindness (less than 10^-4).

    That translates into a total success odds ranging from 94% to 96%. I find those probabilities very acceptable. I commented that these odds are only slightly lower than not having an auto accident going to and from the surgery, especially if my wife is driving. Don’t tell her I said that.

    Thank you for the post.

    Best Wishes.
  • Good luck on your procedure MJG!
Sign In or Register to comment.