Portfolio sorts
Exercises:
- Load the monthly CRSP file, the Fama-French Factors, and the estimated betas from
crsp_monthly.parquet,factors_ff_monthly.parquet, andbeta.parquetindata-r/data-python. - Create portfolio sorts based on the lagged beta. Specifically, you compute the breakpoint as the median lag beta each month. Then, you compute the returns of a portfolio that invests only in the stocks with a higher beta than the breakpoint and a portfolio that invests only in the stocks with a lower beta than the breakpoints. The portfolio weights can either be equal or value-weighted.
- What are the monthly excess returns of both portfolios?
- Does a portfolio that goes long high beta stocks and short low beta stocks yield an excess return significantly different from zero?
- Write a general function for portfolio sorts based on a variable number of breakpoints. Then, compute portfolio returns based on lagged beta decile sorts.
- What is the CAPM alpha of the ten portfolio returns? Is this finding in line with your expectations based on the CAPM implications?
- Does a high beta minus low beta portfolio yield abnormal excess returns?
Solutions: All solutions are provided in the book chapter Univariate portfolio sorts (R Version) or Univariate portfolio sorts (Python Version)