A note on the behaviour of augmented principal-component plots in regression

A simple formula for the augmented principal components of a linear regression model is derived. The formula allows one to explore certain aspects of the behaviour of principal-component plots. A practical example is discussed     

The value of audit quality in public and private companies: evidence from Spain

This paper compares the value of audit quality, proxied by the selection of a big N auditor, to the external claimholders of private and public companies. Although the combination of a lower ownership concentration of public companies, the greater demand for financial information quality about these companies and their higher litigation risk can result in the expectation that audit quality should be more valuable for public than for private companies, the greater information asymmetry between the managers and the external stakeholders and the unavailability of alternative mechanisms for monitoring the managers can make external audit more valuable for the external claimholders of private companies. In this paper, we test these two competing views by analysing if banks and lenders take into account auditor selection in the formation of the cost of debt. Our results support the second view: we find that only private companies obtain a lower cost of debt when they are audited by a high-quality auditor. These results are robust to both endogeneity and unobserved firm-specific heterogeneity.     

A set of independent sequential residuals for the multivariate regression model

In this paper a set of residuals for the multivariate linear regression model is introduced. These residuals are shown to be independent with known distributions which do not depend on the parameters of the model. Transformations of the mentioned residuals may be used to construct exact α goodness-of-fit tests for the multivariate regression model.     

The migratory impact of minimum wage legislation: Puerto Rico, 1970-1987

"This study examines the impact of minimum wage setting on labor migration. A multiple time series framework is applied to monthly data for Puerto Rico from 1970-1987. The results show that net emigration from Puerto Rico to the United States fell in response to significant changes in the manner in which minimum wage policy was conducted, particularly after 1974. The extent of commuter type labor migration between Puerto Rico and the United States is influenced by minimum wage policy, with potentially important consequences for human capital investment and long-term standards of living."     

Demographic drivers of Norway rat populations from urban slums in Brazil

Urban Ecosystems - The Norway rat is a globally distributed pest, known for its resilience to eradication and control programs. Efficient population control, especially in urban settings, is...     

The Manufacturer's Incentive to Reduce Lead Times

Although, ceteris paribus, reducing lead times may be desirable from an overall system perspective, an upstream party (e.g., a manufacturer) may have strong disincentives to offer shorter lead times, even if this came at no cost. We consider a setting in which the downstream party has the ability to exert a costly effort to increase demand (e.g., through sales promotions, advertising, etc.) during the selling season, and compare two situations: one where there is zero lead time (i.e., all demand can be satisfied after observing the demand realization), and one where orders need to be made before demand is realized. We identify two interacting effects that may inhibit shorter lead times. A so‐called “safety stock effect” can be observed when a lower risk of stocking out under short lead times induces the downstream party to alter her order quantity. A second effect, termed as “effort effect,” arises if shorter lead times impact the downstream party's optimal sales effort, and, as a consequence, lead to different order quantities. We provide a formal characterization of both effects, insight into how these effects interact, and show under which conditions the manufacturer has an incentive to offer shorter lead times.