Katrina in historical context: environment and migration in the U.S.

The massive publicity surrounding the exodus of residents from New Orleans spurred by Hurricane Katrina has encouraged interest in the ways that past migration in the U.S. has been shaped by environmental factors. So has Timothy Egan’s exciting book, The Worst Hard Time: The Untold Story of those who survived the Great American Dust Bowl. This article places those dramatic stories into a much less exciting context, demonstrating that the kinds of environmental factors exemplified by Katrina and the Dust Bowl are dwarfed in importance and frequency by the other ways that environment has both impeded and assisted the forces of migration. We accomplish this goal by enumerating four types of environmental influence on migration in the U.S.: (1) environmental calamities, including floods, hurricanes, earthquakes, and tornadoes, (2) environmental hardships and their obverse, short-term environmental benefits, including both drought and short periods of favorable weather, (3) environmental amenities, including warmth, sun, and proximity to water or mountains, and (4) environmental barriers and their management, including heat, air conditioning, flood control, drainage, and irrigation. In U.S. history, all four of these have driven migration flows in one direction or another. Placing Katrina into this historical context is an important task, both because the environmental calamities of which Katrina is an example are relatively rare and have not had a wide impact, and because focusing on them defers interest from the other kinds of environmental impacts, whose effect on migration may have been stronger and more persistent, though less dramatic.     

Understanding information systems infrastructure in engineering SMEs: A case study

The benefits of integrated enterprise-wide information systems (IS), such as Enterprise Resource Planning (ERP) systems, are widely accepted. The implementation of such systems in large organisations is established with many in their second or third generation. However, in small to medium-sized enterprises (SMEs) the maturity and extent of their IS infrastructure is less clear. In engineering SMEs, this infrastructure needs to support not only business processes but also the activities of design and manufacture.In this case study, our goal is to provide a better understanding of current IS infrastructure, the functional elements of IS infrastructure, integration and expenditures are explored in ten engineering SMEs. A model of IS functionality is developed and used to identify and classify functional elements within the firms and to compare and contrast the IS infrastructures. The findings are contrasted with the SME literature and conclusions and implications developed.     

The Technologisation of Childhood? Young Children and Technology in the Home

We describe an 18-month empirical investigation of three- and four-year-old children's uses of technology at home, based on a survey of 346 families and 24 case studies. The findings are reported in the context of social commentators' anxieties about the ways in which childhood is being transformed by technology. Although we report evidence of some parental disquiet about the role of technology in children's lives, we illustrate some of the complexities in families' attitudes to, and uses of, technology and conclude that it is not perceived by parents to be the threat to modern childhood that is claimed.     

Changes in Risk Perceptions Prospectively Predict Changes in Self‐Reported Speeding

Risk perception theories posit that changes in risk perception prompt subsequent changes in risk behavior. Prospective studies using observations made at three time‐points offer the capacity to test this hypothesis by observing sequential changes in both risk perceptions and behavior. A telephone survey was administered by random‐digit dialing to 255 adult Australian drivers at baseline (T1), 6 weeks (T2), and 14 weeks (T3). During weeks 2–5, a risk‐perception‐based anti‐speeding mass media campaign was conducted. The survey assessed risk perception, operationalized as the proportion of time that driving at 70 km/h (43 mph) was perceived to be dangerous, and self‐reported speeding behavior, defined as the frequency of respondents driving 5 km (3 mph) faster than the legal speed limit in built up areas. Higher T2 risk perception predicted lower T3 self‐reports of speeding after controlling T1 risk perception and T1 and T2 self‐reported speeding. This can be interpreted as changes in risk perceptions between T1 and T2 predicting changes in speeding between T2 and T3. Further analyses showed that increases in risk perception predicted lower subsequent self‐reported speeding changes, but decreases in risk perception were unrelated to those changes. Risk perception changes were unrelated to recall of exposure to the media campaign. These findings support a dynamic view of the relationship between risk perception and self‐reported behavior, and that risk perception theories can be applied to speeding.     

A Comparison of Ethical Practices of Russian and American Managers

This study examines perception of various business practices of Russian and American managers. Using data collected from 136 Russian managers and 252 American managers we found that cross-national differences account for many differences between perceptions of business practices. Implications for managerial practice are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

A new special class of peb designs

A new class of partially efficiency-balanced designs is introduced from a practical point of view. This new design includes all equireplicated incomplete block designs available in literature as special cases. The fundamental properties of the design are clarified with relation to other block designs.     

On a nonparametric test for the mixed-model

Nonparametric tests for the null hypothesis of no treatment effect in the mixed-model experiment which involves n randomly chosen subjects who respond once to each of ρ distinct treatments have been developed by Koch and Sen (1968), These tests were based on the assumption of compound symmetry of the error vectors and on the weaker assumption of diagonal symmetry of the error vectors. This paper considers an alternative (permutationally) distribution-free test under this latter assumption. The new test follows the same type of distribution theory as those in Koch and Sen, but utilizes the inherent invariance structure in a more visable and direct way.     

Univaiuate anu multivariate categorical data analysis for block designs

Analysis for univariate and multivariate categorical data in block designs is given and illustrated through examples. The univariate analysis compares the treatments on the basis of their pooled frequency distributions (pooled over blocks). The test statistic used is called Q after Cochran (1950). The large sample null distribution of Q is a chi-square. Analysis of p-variate categorical data (kth variable having ck classes, K=1,...,p) can be done by treating it as a univariate categorical problem with [d] classes. Very often [d] is large in relation to the size of the experiment. This makes the expected frequencies for some of the cells very small, making the univariate method inapplicable. In these circumstances it may be reasonable to compare the treatments on the basis of marginal distributions up to the mth dimension, 1[d] , which is given in this paper. This method is also illustrated for missing observations