If you're in a disagreement with someone and he sends you links to research explaining his position and adding nuance, please don't ignore the e-mail and then continue with your original criticism.
Thanks very much!
</public service announcement>
(Although you may not realize it, criticizing and then ignoring the other person's perspective effectively makes the conversation one-sided, even though both people may appear to be continuing to talk.)
On a practical level, I think something like this happens whenever diversification-based approaches like risk parity and factors are brought up.
Those are automatically 'wrong' because there is only one valid approach (cap-weighted U.S. stocks with a sprinking of Treasuries.)
In other words, the objection is essentially religious.
That doesn't make it wrong or completely subjective. It just means that it involves a presupposition that overrides everything else... so you better be sure your belief is truly worthy of your trust.
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1/ Superforecasting: The Art and Science of Prediction (Tetlock, Gardner)
"Foresight isn’t a mysterious gift bestowed at birth. It is the product of particular ways of thinking, of gathering information, of updating beliefs." (p. 18)
2/ "The news delivers forecasts without asking how good the forecasters really are. Corporations and governments pay for forecasts that may be prescient, worthless, or something in between. All of us make critical decisions based on forecasts whose quality is unknown." (p. 3)
3/ "Pundits are not on the news because they possess proven skill at forecasting. Old forecasts are like old news—soon forgotten. Pundits are not asked to reconcile what they said with what happened later.
"Talking heads are skilled at telling a compelling story with conviction.
"My brother bought silver coins at a premium of 20% over face value. It was an asymmetric risk trade: you could lose a maximum of 20%, but the upside was unlimited.
"By 1974, silver had more than tripled. My brother was driving around in a Mercedes-Benz." (p. 7)
3/ "Charts have become much less reliable. In the 1970s-80s, patterns were neat. There were fewer whipsaws. There weren’t a lot of people looking at charts.
"I think high-frequency trading creates volatility around breakout points. Markets are more mature, with bigger players.
1/ I've been getting e-mails "encouraging" me to vote one way or the other... this is how I've responded:
There is a lot of research over the past sixty years suggesting that people think prediction is much easier than it actually is (for both sides of the political spectrum).
2/ We anchor on pieces of information that are easy to remember because we've seen them in the news, but those are not a randomly chosen sample (so unsuitable for making predictions). They are also such a small sample that it's hard to draw statistically significant conclusions.
3/ "The problem is that it *feels* like a random sample and *feels* like a large enough sample, so the more information that people receive, the more overconfident they become, and (ironically) the worse their predictions get.
"Contrary to stock-level evidence, we find a short-term momentum pattern in five major asset classes: the most recent month’s return positively predicts future performance."
2/ Asset classes: Equities, bonds, bills, commodities, and currencies
Sample period: 1800-2018
Data converted to U.S. dollars
For commodities, *spot* prices are used
"The aggregate number of assets increases gradually from 16 in January 1800 to more than 250 in the final years."
3/ Short-term momentum (SMOM) = asset return in month t-1
For control variables: "Due to our data limitations, we must be able to derive the variables using only price information, i.e., without any additional use of accounting data, investor positions, credit ratings, etc."