Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The set of parameters needed to calculate the expected present discounted value of a stream of dividends can be estimated in two ways. One may test for speculative bubbles, or fads, by testing whether the two estimates are the same. When the test is applied to some annual U. S. stock market data, the data usually reject the null hypothesis of no bubbles. The test is of general interest, since it may be applied to a wide class of linear rational expectations models.