Time-Series Coefficient Variation in Value-Relevance Regressions : A Discussion of Core, Guay, and Van Buskirk and New Evidence

Many claim that GAAP financial information has become largely irrelevant to explaining valuations. Core et al. compare financial information's value relevance for the New Economy stocks with other stocks. We supplement their analysis with new evidence on the economic determinants of the time-series variation in the coefficients mapping financial information into prices. We document significant variation in the coefficients related to proxies for changing market growth expectations and discount rates and additional variation consistent with time-varying correlated omitted variables. Such findings make it difficult to draw unambiguous inferences about the relevance and reliability of financial information from value-relevance regressions