Some characteristics of the Canadian audit industry*

Abstract. We examine some of the basic issues concerning concentration, the level of competition, and returns to scale in the Canadian audit industry. Our findings indicate that it may be more appropriate to construct the concentration indexes in terms of the “Big Seven” instead of the traditional “Big Eight” firms. The results also indicate that the industry is subject in the long run to constant returns to scale and imply fairly competitive markets for audit services.     

THE EFFECTIVENESS OF MINIMUM-WAGE INCREASES IN REDUCING POVERTY: PAST, PRESENT, AND FUTURE

Extending the work of Card and Krueger, we find minimum-wage increases (1988–2003) did not affect poverty rates overall, or among the working poor or among single mothers. Despite employment growth among single mothers, most gainers lived in nonpoor families and most working poor already had wages above the proposed minimums. Simulating a new federal minimum wage of $7.25 per hour, we find 87% of workers who benefit live in nonpoor families. Poor single mothers receive 3.8% of all benefits. Expanding the Earned Income Tax Credit would far more effectively reduce poverty, especially for single mothers. ( JEL J21, J31, J38)     

A Non-Parametric Test of Exogeneity

This paper presents a test for exogeneity of explanatory variables that minimizes the need for auxiliary assumptions that are not required by the definition of exogeneity. It concerns inference about a non-parametric function g that is identified by a conditional moment restriction involving instrumental variables (IV). A test of the hypothesis that g is the mean of a random variable Y conditional on a covariate X is developed that is not subject to the ill-posed inverse problem of non-parametric IV estimation. The test is consistent whenever g differs from E ( Y | X ) on a set of non-zero probability. The usefulness of this new exogeneity test is displayed through Monte Carlo experiments and an application to estimation of non-parametric consumer expansion paths.