Toward Improving Food Safety in the Domestic Environment: A Multi-Item Rasch Scale for the Measurement of the Safety Efficacy of Domestic Food-Handling Practices

To reduce consumer health risks from foodborne diseases that result from improper domestic food handling, consumers need to know how to safely handle food. To realize improvements in public health, it is necessary to develop interventions that match the needs of individual consumers. Successful intervention strategies are therefore contingent on identifying not only the practices that are important for consumer protection, but also barriers that prevent consumers from responding to these interventions. A measure of food safety behavior is needed to assess the effectiveness of different intervention strategies across different groups of consumers. A nationally representative survey was conducted in the Netherlands to determine which practices are likely conducted by which consumers. Participants reported their behaviors with respect to 55 different food-handling practices. The Rasch modeling technique was used to determine a general measure for the likelihood of an average consumer performing each food-handling behavior. Simultaneously, an average performance measure was estimated for each consumer. These two measures can be combined to predict the likelihood that an individual consumer engages in a specific food-handling behavior. A single "food safety" dimension was shown to underlie all items. Some potentially safe practices (e.g., use of meat thermometers) were reported as very difficult, while other safe practices were conducted by respondents more frequently (e.g., washing of fresh fruit and vegetables). A cluster analysis was applied to the resulting data set, and five segments of consumers were identified. Different behaviors may have different effects on microbial growth in food, and thus have different consequences for human health. Once the microbial relevance of the different consumer behaviors has been confirmed by experiments and modeling, the scale developed in the research reported here can be used to develop risk communication targeted to the needs of different consumer groups, as well as to measure the efficacy of different interventions.     

Proportional subclass numbers in two-factor ANOVA

The between-within split of total sum of squares in one-way analysis of variance (ANOVA) is intuitively appealing and computationally simple, whether balanced or not. In the balanced two-factor setting, the same heuristic and computations apply to analyse treatment sum of squares into main effects and interaction effects sums of squares. Accomplishing the same in unbalanced settings is more difficult, requiring development of tests of general linear hypotheses. However, textbooks treat unbalanced settings with proportional subclasss numbers (psn) as essentially equivalent to balanced settings. It is shown here that, while psn permit an ANOVA-like partition of sums of squares, test statistics for main effects of the two factors generally test the wrong hypotheses when the model includes interaction effects.     

Fitness profiles and activity patterns of entering college students.

Fitness levels of American youth have shown a marked decline in the last decade, according to recent studies. To determine whether such a tendency persists for entering college students, the authors evaluated 115 male and 143 female students for performance on the following fitness-related variables: (1) maximal oxygen consumption (estimated from Astrand cycling protocol), (2) body composition (skin-fold techniques), (3) muscle endurance (sit-up protocol), (4) muscle strength (bench-press protocol), and (5) joint flexibility (upper and lower body protocols). Although neither men nor women exhibited high levels of cardiorespiratory fitness, the women in the study showed higher relative levels than their male counterparts. Both groups showed excellent levels of muscle strength (compared with normative standards), but they achieved only an average standard for muscle endurance. Findings of relatively low levels of cardiovascular fitness compared with levels of muscle strength, particularly in men, seem to be a reflection of an inappropriate concentration of physical activity.     

DEXPERT: an expert system for the design of experiments

DEXPERT is an expert system, built using KEE, for the design and analysis of experiments. From a mathematical model, expected mean squares are computed, tests are determined, and the power of the tests computed. Comparisons between designs are aided by suggestions and verbal interpretations provided by DEXPERT. DEXPERT provides a layout sheet for the collection of the data and then analyzes and interprets the results using analytical and graphical methods.     

Job insecurity and coworker support among U.S. Workers

Abstract

The negative outcomes associated with job insecurity have been well established in the literature. Yet, scholars know very little about how job insecurity is related to coworker relationships in the workplace. Informed by the life stress perspective, this study examines the relationship between job insecurity and coworker support among U.S. workers. It also considers whether relationships diverge by gender. We use data from a nationally representative sample of U.S. workers (N?=?2,822) to examine these relationships. The results showed that job insecurity was negatively related to coworker support among both men and women, with no evidence of gender disparities. Altogether, the findings suggest job insecurity is damaging to the workplace environment, creating barriers to supportive coworker relationships among both men and women.     

Understanding the planner’s role in lookahead construction planning

Capacity planning is instrumental in production planning as the variability witnessed in construction projects complicates the planner’s role in achieving a balance between weekly task load and available resources. The purpose of this article is to assess the effects of capacity planning on a project’s time and cost performance and to inform planners on the pitfalls of uninformed capacity planning. A simulation model is developed to test several project scenarios against different capacity planning methods. Cost, time and planning quality measures are developed to track project’s performance throughout the construction period. Results show that the planner’s choice of capacity planning method and the type of project both affect a project’s cost and duration. Interestingly, informed planners who are aware of a project’s characteristics are able to achieve the best balance between weekly load and capacity. They are able to reduce incurred costs wasted on idle resources without significantly affecting the construction period.