On Measuring Convergence in the Use of Time

In the study of the effects of retirement on the allocation of time, this paper discusses methods that evaluate convergence in patterns of time use. Scalar measures of multivariate scatter are revealed to be a more general method than previous devices utilized in the time-use literature. However, since time devoted to some activities could be correlated with time devoted to others, the degree of scatter observed in the data tend to be affected by the level of activity aggregation selected by the researcher.

ON THE PRICE OF RECREATION GOODS AS A DETERMINANT OF MALE LABOR SUPPLY

This paper examines whether and how changes in the price of goods consumed in conjunction with leisure time influence the life-cycle allocation of work effort by part of prime-age males. For the U.S., individual-level data is combined with Metropolitan Area-level price indices of recreation goods to estimate the male elasticity of intertemporal substitution of market time with respect to the price of recreation goods, which is found to be centered at 0.18 and statistically different from zero. The allocation of work effort over the life-cycle in response to changes in the price of recreation goods creates movements in the output of an economy that could be important for understanding economic fluctuations.Intertemporal substitution, male labor supply, panel data.

Montane environments as a source of biotypic diversity in Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), in Colorado

2013 Summer.Includes bibliographical references.The Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), is a small grain pest of worldwide economic importance. The preferred hosts of the Russian wheat aphid are wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and triticale (X Triticosecale Wittmack). The aphid also colonizes noncultivated cool-season grasses, particularly wheatgrasses, and volunteer wheat and barley plants. This pest also has been found on different grass species at elevations between 1,000 and 3,000 m above sea level in Colorado. The objective of this study was to improve our knowledge of Russian wheat aphid biotypic diversity present along the Front Range of northern Colorado. In order to achieve this objective I compared the biotypic diversity of Russian wheat aphids present on alternate grass hosts (crested wheatgrass, intermediate wheatgrass, slender wheatgrass, western wheatgrass and foxtail barley) in montane and prairie environments using plant differentials (wheat and barley lines) currently of interest to the Colorado State University wheat breeding program. The ultimate goal was to determine if noncultivated grass hosts in montane environments are a potential source of the biotypic diversity of Russian wheat aphid affecting wheat production in eastern Colorado. Fourteen Russian wheat aphid isolates were collected in 2010 from prairie and montane sites and characterized in a standard seedling assay using 22 wheat and two barley lines with known reactions to biotype 1 Russian wheat aphid (RWA1) and biotype 2 Russian wheat aphid (RWA2). Thirty-four Russian wheat aphid isolates were collected in 2011 and characterized in a standard seedling assay using seven wheat and one barley lines with know reactions to the RWA1 and RWA2 biotypes. Known biotypes RWA1 and RWA2 were included for comparison. Once the RWA1 susceptible wheat cultivar 'Yuma' and barley cultivar 'Otis' were killed, all plants were rated for leaf chlorosis and leaf rolling. Differences in virulence patterns were observed among the 14 isolates from 2010 and the 34 isolates from 2011 for leaf chlorosis and leaf rolling. The isolates exhibited different levels of damage, and divided into three groups: isolates producing low amount of damage (similar to that expected by biotype RWA1 on plants expressing Dn4 resistance), isolates producing heavy damage (similar to that expected from biotype RWA2 feeding on susceptible plants or plants expressing Dn4 resistance), and isolates with intermediate level of damage. Isolates M5 and P14, collected in 2010, produced more damage than the RWA2 biotype. Isolate M5 produced heavy damage on CO03797, Karee-Dn8, Betta-Dn9, and intermediate damage on 94M370 and Sidney, whereas RWA2 biotype produced intermediate damage on CO03797, Karee-Dn8, and Betta-Dn9, and low amount of damage on 94M370 and Sidney. Isolate P14 produced heavy damage on Karee-Dn8 and intermediate damage on 94M370, whereas RWA2 biotype produced intermediate damage on Karee-Dn8 and low amount of damage on 94M370. Collection date and site did not influence damage in either 2010 or 2011 isolates. For example, isolates M5, M2, M3 and M4 from 2010 were all collected from the same montane site on the same date, but were categorized into three damage groups. Isolates M40, M36 and M37 were also collected from the same montane site on the same date in 2011, but represented two damage groups. The results of these screenings confirmed the presence of two previously unknown biotypes: isolate M5, collected from a montane site, and isolate P14, collected from a prairie site. Both biotypes were more virulent than RWA2 biotype. These results also documented that biotypic diversity of Russian wheat aphid in Colorado montane was greater than the prairie collections

Promoting Health: An Instrument of Power and an Emancipatory Alternative

Objectives: There are three central objectives in this work. The first is to offer a critical panorama of the promotion of health which serves as a reflection of who is interested in this field. The second is to present an emancipatory interpretation of health promotion. The third is to invite the construction of such emancipatory health promotion

On Measuring Convergence in the Use of Time

In the study of the effects of retirement on the allocation of time, this paper discusses methods that evaluate convergence in patterns of time use. Scalar measures of multivariate scatter are revealed to be a more general method than previous devices utilized in the time-use literature. However, since time devoted to some activities could be correlated with time devoted to others, the degree of scatter observed in the data tend to be affected by the level of activity aggregation selected by the researcher

Is there a patience premium on migration?

The very few studies on the empirical link between time preference and migration involve small samples or do not control for cognitive skills. This study uses data from a large, nationally representative survey with information on time preferences and cognitive skills to investigatewhether cross-region migrants in Spain are less impatient than individuals who choose to remain in their birth region. The empirical model incorporates predicted probabilities of misclassifying lifetime migrant status. The results suggest that the effect of impatience on the likelihood of migrating internally is negative but decreasing, and that it is smaller than the effect on the likelihood of migrating abroad

Split or straight? Evidence of the effects of work schedules on workers’ well-being, time use, and productivity

About half of all employees in Spain are on a daytime split work schedule, i.e. they typically work for 5 h in the morning, take a 2-hour break at lunch time, and work for another 3 h in the afternoon/evening. This paper studies the effects of split work schedule on workers’ psychological well-being, daily time use, and productivity. Using cross-sectional data from the 2002 to 2003 Spanish Time Use Survey, I find that female split-shifters experience an increased feeling of being at least sometimes overwhelmed by tasks and not having enough time to complete them. On working days, a split work schedule is positively related to time spent on the job, sleeping, and eating and drinking, and negatively associated with time spent on housework, parental child care, and leisure activities. Most of the time-use effects are similar across the sexes, and only a few of the time reductions are partly made up on days off. I also find that the split work schedule is associated with lower hourly wages

Patience goes a long way: Evidence from Spain.

This study uses newly available data from the Survey of Financial Competences to investigate whether cross-region migrants in Spain are more patient than individuals who choose to remain in their birth region. The empirical model incorporates predicted probabilities of underreporting and overreporting of the migrant status. Less patient individuals appear to be less likely to be migrants. This result is robust to controlling for a variety of demographic and economic factors, as well as for cognitive ability

Patience goes a long way: Evidence from Spain.

This study uses newly available data from the Survey of Financial Competences to investigate whether cross-region migrants in Spain are more patient than individuals who choose to remain in their birth region. The empirical model incorporates predicted probabilities of underreporting and overreporting of the migrant status. Less patient individuals appear to be less likely to be migrants. This result is robust to controlling for a variety of demographic and economic factors, as well as for cognitive ability