Residual variables in regression and confluence analysis

Abstract

Let be the regression of X ₁ on X ₂, X ₃,… X_n (also called the first elementary regression in the set of variables X ₁, X ₂,…,X_n ).     

Is cannabis a gateway to hard drugs?

The gateway hypothesis proposes that use of cannabis directly increases the risk of consuming hard drugs. We test this controversial, but influential, hypothesis on a sample of cannabis users, exploiting a unique set of drug price data. A flexible approach is developed to identify the causal gateway effect using a bivariate survival model with shared frailty estimated using a latent class approach. The model suggests two distinct groups; a smaller group of “troubled youths” for whom there is a statistically significant gateway effect that more than doubles the hazard of starting to use hard drugs and a larger fraction of youths for whom previous cannabis use has less impact.     

Social networks and the geography of entrepreneurship

Social relationships play at least three important roles in entrepreneurship. They help to determine who sees entrepreneurship as an available and desirable career path. Entrepreneurs use their contacts to raise funds for and to recruit employees and partners to their ventures. Social relationships also influence where and when entrepreneurs want to spend their leisure time. Because of these factors, entrepreneurs tend to found their firms in the places that they live (and in the industries in which they have been employed). That, in turn, implies that industries will tend to become and remain concentrated in a small number of places, even when firms do not benefit from this clustering.     

Niche width revisited: organizational scope,behavior and performance

Although strategy research typically regards firm scope as a positional characteristic associated with performance differences, we propose that broad contemporary scope also provides insight into the routines that govern firm behavior. To attain broad scope, firms must repeatedly explore outside the boundaries of their current niche. Firms with broad niches therefore operate under a set of routines that repeatedly propel them into new market segments, expanding their niche. These niche expansions, however, involve risky organizational changes, behavior that disadvantages generalists relative to specialists, despite the positional value of broad scope. Empirical analyses of machine tool manufacturers and computer workstation manufacturers support this conjecture: (i) generalists introduce new products at a higher than optimal rate, thereby increasing their exit rates; and (ii) generalists also more frequently launch new models with novel features or targeted at new consumer segments rather than improving only incrementally on existing products, further accelerating their odds of failure. After adjusting for these behavioral differences, broad niche widths reduce exit rates, suggesting that they provide positional advantages. The paper discusses how this phenomenon may help to explain the diversification and multi‐nationality discounts. Copyright © 2006 John Wiley & Sons, Ltd.     

Biases in the selection stage of bottom‐up strategy formulation

We propose that the failure to adopt an idea or innovation can arise from an in‐group bias among employees within an organizational subunit that leads the subunit's members to undervalue systematically ideas associated with members of the organization outside their subunit. Such biases in internal selection processes can stymie organizational adaptation and therefore depress the performance of the firm. Analyzing data on innovation proposals inside a large, multinational consumer goods firm, we find that evaluators are biased in favor of ideas submitted by individuals that work in the same division and facility as they do, particularly when they belong to small or high‐status subunits. Copyright © 2013 John Wiley & Sons, Ltd     

Purchases and complaints: A logit-model analysis

This article treats the individual purchase as an event produced by the household. It is hypothesized that household resources and perceived product importance will be positively related to the probability of making overt complaint for a given purchase. It is also hypothesized that purchases made in the private market more than purchases made in the public supply system will be subject to overt complaints. A logit-model analysis based on 1,640 purchases supported the resource and supply system hypotheses, but failed to support the product-importance hypothesis.     

A new basis of calculation for collective pensions insurance in Norway

The writing of collective pensions insurance in Norway was first taken up in 1917 by the “Norske Folk”, a life insurance company, founded by the seven oldest Norwegian life insurance companies, and a short time afterwards this kind of insurance was also taken up by the “Norske Forenede”. Finally, in 1931, the “Samvirke” which had been established a short time before by the Norwegian Cooperative Association, began to write collective pensions insurance.     

Mitigating theoretical and coverage biases in the design of theory-building research: an example from international entrepreneurship

In this paper, we advance a three-stage theory-building framework to assist scholars in addressing theoretical and coverage biases by means of the appropriate design of cross-domain theory-building research. In our discussion, we use an example from research in international entrepreneurship, which has been emerging as a cross-domain area for the entrepreneurship and international business research communities since the mid-1990s. Theoretical bias can stem from the situation where the conceptualisation of a phenomenon whose research is currently emerging and depends upon several of the established disciplines of social science and their sub-domains, is in fact dominated by the theoretical approaches of a single domain. As to the coverage bias, the somewhat novel research domain of international entrepreneurship provides us with a means to illustrate how research in an emerging domain tends to focus on positive growth only and rarely takes appropriately into account companies that fare less well; for instance, accounting for survivor bias would require that scholars carefully acknowledge firms that go out of business for one reason or another. Observations from a longitudinal, multiple-case study research on the de-internationalisation of small high-technology firms is used to exemplify the structure of our framework.