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Jim O'Shaughnessy @jposhaughnessy
, 5 tweets, 1 min read Read on Twitter
Revisiting this, very illuminating: The Most Dangerous Equation.

citeseerx.ist.psu.edu/viewdoc/downlo…
1/From original notes:
In systems dominated by skill, feedback is clear and accurate. In systems where luck plays a role, good decisions can lead to failure and bad ones to success. Any activity that combines luck and skill is mean reverting.
2/ Studies in educational reform found that small schools had the best results. Billions were spent reducing school and class size. Did no good. Closer examination of the data on smaller schools found they also had the WORST scores. Sample size mislead.
3/Our brains construct cause/effect narratives AFTER something happens. No matter how improbable, we construct narrative to explain why it happened.
Post hoc, ergo propter hoc. en.wikipedia.org/wiki/Post_hoc_…
fin
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1/ Markets change minute-by-minute.
Human nature barely changes millennium-by-millennium.
There's your edge.
How To Arbitrage Human Nature: A thread
2/ People want to believe the present is different than the past. Markets are now computerized, high-frequency and block traders dominate, the individual investor is gone and, in his/her place, sit a plethora of huge mutual funds and hedge funds to which he has given his money.
3/ Many have simply given up trying to earn alpha in the market and have given their money to index funds. Some people think these masters of money make decisions differently and believe that looking at how a strategy performed in the 1950′s or 1960′s offers
Read 19 tweets
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12/ the market on 16 occasions. As Dreman dryly notes: “This meant, in effect, that when a client received professional advice about those stocks, they would underperform the market almost nine times out of ten.” Finally, many studies have shown that this is true in almost
13/ all forecasts, be they about stock prices, patients needing medical treatment, college admissions offices trying to pick who to admit–and virtually every other industry where professionals were making predictions and forecasts. And yet, even with all of this empirical
14/ data, we continue to crave forecasts and put a lot of faith in them. Why? Human nature. We abhor not knowing what might happen and crave continuity and certainty. Thus, we tend to grasp on to anything that sounds reasonable and often end up following a narrative that leads
Read 4 tweets
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1/ Successful Active Investors Generally Ignore Forecasts and Predictions.

“I have no use whatsoever for projections or forecasts. They create an illusion of apparent precision. The more meticulous they are, the more concerned you should be.”
~Warren Buffett
2/ You can’t turn on business TV or read all of the various business news outlets or even talk with other investors without being bombarded with both short- and long-term forecasts and predictions. Against all the evidence, forecasts and predictions about what might happen in
3/ the future are intuitively attractive to us, since we are desperate to have a narrative about how the future might unfold. We tend to extrapolate what has happened recently well into the future, which almost never works. We’ll explore the results of this in a minute,
Read 11 tweets

Related threads

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The Rupee reached an all time low against US Dollar in Sep 2018 hitting close to 73 units to a dollar

But this fall in the rupee has coincided with one of the strongest phases of the Indian economy ever

An economy growing at a faster clip than it ever has in the past 4000 years
For those who are naive about the role of currency and monetary standards this may have seemed perplexing.

How can the economy be doing so well at a time when the country’s monetary unit is at its weakest.
While this question is no doubt naive it remains very seductive.

Most intelligent people would have this gut-feel that a country’s economic health mustn’t be judged by the state of its currency unit, but they may struggle to articulate why people who feel otherwise are wrong
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Global network of Five Eyes surveillance bases
#Qanon #EndTheFed
Worldwide SIGINT/Defense Cryptologic Platform
#Qanon #EndTheFed
Approved SIGINT Partners (Notice United Arab Emirates is on the list...)
#Qanon #EndTheFed
Read 46 tweets
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Candidate Arrested After Exposing Opponent’s Ties To Terrorist Group centralfloridapost.com/2018/08/07/can… via @CFLpost
She used to be a member of Fox and Rumanni PA.

lawyercentral.com/amira-dajani-f…
Steve Rumanni was a member there also.

lawyer-map.com/Ramunni_Steven…
Read 71 tweets
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1/ Why didn't America act on climate change way back when?

You've read the historical reconstruction in the @NYTmag of the 1980s, the decade when the science was becoming clearer and there was some bipartisan political momentum to act.

There's more to this story.
2/ The tale of U.S. climate inaction spans 70 years and it continues to this day. insideclimatenews.org/content/climat…
3/ Denial of mainstream climate science has developed into a core message of the Republican party, now in control of the White House and Congress. The narrative of how we got here is complicated.
Read 39 tweets
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1/ Thread - New Hampshire is 94% White

What's wrong with that?
2/ Of course, the article is behind a paywall, which I am sure is somehow racist.

If you want a #quickrundown, you can find it here:

twitchy.com/brettt-3136/20…
3/ The real underlying issues are related to population dynamics - an ageing workforce approaching retirement age requires more young workers to keep the social safety net (ponzi scheme) going.

But, the failing New York Times decides to blame it on race.
Read 29 tweets
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I just watched @mfeathers "Unconditional Code", where he proposes redesigning code to not have "error states" as valid paths. This contrasts with option types / exceptions.

"Comparing" the three reminds me of an obscure idea in SE: Problem Frames.

You're prob familiar with the inverse of PFs: Patterns. A "pattern" is a means of classifying solutions to a problem, like strategies or dispatch tables. A "problem frame", on the other hand, is a means of classifying _problems_, for a specific usage of "problems".
Michael Jackson (not the singer) defined software development as the relation between our system (the 'machine'), reality (the 'world'), and the intentions of the users (the 'requirements'). The 'problem', then, is building a machine that unifies the world and the requirements.
Read 6 tweets

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