Thursday, April 23, 2015

"Are Value Investing and Momentum Investing Robust Anomalies?"

One of the few examples where Betteridge's Law of Headlines is not operative and the answer is Yes.
From Alpha Architect:

Beating a Dead Horse: Value investing and momentum investing work

At this stage in our lives we’ve essentially memorized the CRSP/Compustat database. Name an anomaly and we can probably tell you the stats on it fairly quickly.
Legitimate anomalies can usually be described via a behavioral finance lens:
  1. Can we identify poor psychology in the market? (Why do prices get dislocated along the way)
  2. Can we identify the limits to arbitrage? (Why don’t large pools of capital arbitrage the anomaly away)
There are 2 anomalies that stand out among all other anomalies: Value investing and momentum investing.
But don’t take our word for it, check out one of my favorite papers on the subject of “anomaly chasing:”
…and the Cross-Section of Expected Returns
http://blog.alphaarchitect.com/wp-content/uploads/2015/04/val_mom.png
You can find the entire laundry list of the papers examined here.

The authors argue that published papers suffer from serious data-mining efforts, and therefore, we need to adjust our statistical inference metrics to account for this fact....MORE