In an earlier article in this Journal, Horwitz and Kolodny reported that imposition of the SEC's line of business reporting requirements did not affect investors' assessments of the riskiness of multisegment firms. We suggest that shortcomings in their sample-selection and hypothesis-testing...

This paper reexamines the issue of common stock market risk stationarity by applying a newly available exact test for random-walk regression coefficients. For each eight-year subperiod tested in the 1951–1974 interval, betas for individual New York Stock Exchange-listed stocks appeared to be...