The Value of Television Time:Some Problems and Attempted Solutions,

摘要

The relative magnitude of the estimated coefficients is such that the equation anomalously implies that adding a station to a market sometimes increases time RATEs of stations already in the market. The equation does nothing at all to explain time RATEs for independent UHF stations. A simultaneous equations (TSLS) approach produces an estimated equation that looks even better than Besen's, and pretty well straightens out the anomalous implications. This exercise points up two important lessons. (1) High R-squared and t-statistics do not guarantee a problem-free equation. (2) Coefficients may (probably do) differ between natural subsamples. The hypothesis that they are the same should always be tested.