Knowledge that Transforms

This paper is concerned with the validity of the conventional t tests on regression coefficients when there is serious multicollinearity between the explanatory variables. It is well known that increasing multicollinearity causes the true standard errors of regression coefficients to rise. The crucial question, however, is whether the conventional formulas will in practice reflect this rise. The purpose of this note is to show that the conventional t tests will in practice reflect this rise. But this note also points out the danger involved in mechanically dropping variables from multiple regression equations by t tests because t values of the regression coefficients may not be significantly different from zero when the true (population) values of these coefficients are in fact not zero, if the explanatory variables are highly intercorrelated.

In testing hypotheses, researchers are almost always faced with the problem of isolating the effect of certain variables. This is a particularly acute problem in the social sciences, where the absence of an experimental environment means that researchers must resort to statistical methods of adjustment.

Individual decisions about investment may be regarded as choices among alternative probability distributions of net returns. It is assumed that these distributions are completely known and independent of initial wealth positions, and that individuals determine the preferred portfolio of investment in accordance with a given, consistent set of preferences.

This paper applies a single measure of investment performance to mutual fund portfolios for the 20-year period 1948–1967. It criticizes the efficacy of market indices, at least for the purpose of evaluating aggregate results of managed portfolios; it tests the predictive value of past results in forecasting future performance; and finally, it identifies two factors that are positively related to fund performance during the time period studied.

Markowitz's [2] portfolio selection model was originally concerned with financial investments, but the model's implications for capital budgeting are now well recognized. Markowitz's basic idea is that the optimal portfolio for an investor is not simply any collection of good securities, but a balanced whole, providing the investor with the best combination of “return” and “risk.” Return and risk are to be measured by the expected value and variance of the probability distribution of portfolio return. Although financial writers have generally accepted Markowitz's measure of return, they have not been completely satisfied with his suggested measure of risk [1]. In fact, Markowitz himself had reservations about choosing variance as a measure of risk.1 Besides variance, he considered five other alternative measures of risk:(1) The expected value of loss;(2) The probability of loss;(3) The expected absolute deviation;(4) The maximum expected loss; and(5) The semivariance.

A great deal of interest has been expressed by economists and policy-makers concerning the adequacy of the financing of small and, especially, new firms. This paper presents an empirical study of the adequacy of one particular source of funds—outside equity.

An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

An abstract is not available for this content so a preview has been provided. Please use the Get access link above for information on how to access this content.