Risk measurement when shares are subject to infrequent trading: Comment

When securities are thinly traded OLS techniques yield biased beta estimates. Procedures for calculating consistent estimates are proposed by Scholes and Williams (1977) and by Dimson (1979). This comment examines both procedures and concludes that the Dimson procedure is incorrect and cannot generally be expected to yield consistent beta estimates. However, a variant of this procedure can yield results which are identical to Scholes and Williams' and is, therefore, correct.     

An early pricing model regarding the value of a cat: A historical note

Have you ever worried about how much your cat was worth? The ancient Welsh had a formalized system for cat valuation. This system, however, illustrates that the Welsh recognized and faced many of the same vexing problems facing today's valuation theorists.     

A BIAS-CORRECTING PROCEDURE FOR BETA ESTIMATION IN THE PRESENCE OF THIN TRADING

In this paper, an alternative technique is developed for obtaining consistent estimates of beta in the presence of thin trading. The new estimator is tested on simulated data and the results are compared with those obtained from the Dimson [ 4 ] Scholes and Williams [ 9 ] techniques. The new estimator is found to have approximately the same bias as the others, but it has a considerably lower variance.     

Technical Development and the Innovation Process

Independent and small-business inventors face enormous difficulties as they attempt to commercialize new technologies. Harold Livesay, Marcia Rorke and David Lux share a number of their useful insights based on their experience. They find that many inventors wish to focus only on certain aspects of their emerging programs. In fact, these inventors resist the need to develop a balanced program involving not only technical development but also marketing and the creation of sustaining business structures. This article provides a systematic elaboration of these difficulties, suggests a more balanced approach and thus describes a process of education and communication that may increase overall effectiveness.