498 research outputs found
The "Unintended Consequences" of Confederate Trade Legislation
The immediate purpose of this paper is to focus on how import and blockade regulations enacted by the Confederacy affected the course of the war in its final days, but the issue of the economic effects of blockades has broader implications. Economic policies have been used as weapons, at least since the times of Pericles' Megaran Decree in 432 B.C., and have probably only grown in importance as economies have grown less autarkic and more interdependent over time. Since 1790, there have been at least four major global wars that have involved prolonged fighting, heavy losses, and severe bouts of inflation: the Napoleonic Wars, the American Civil War, World War I, and World War II. In all four of these conflicts, embargoes and blockades were an important component of the war planning of the eventual victor.Macroeconomics; Transitional Economies
Household Production and Consumption of News-Information Services: An Empirical Study
A dramatic decline in newspaper consumption has been observed in recent years. This paper offers a theoretical justification for this phenomenon based on the opportunity cost of household time. A rising labor force participation rate, which proxies the opportunity cost of household production, helps explain the observed decline in newspaper consumption in a simple empirical test.Household Production; Households; News; Newspapers; Service; Services
Railroads, engineers, and the developement of spatial economics in France
This articles traces a little-known French tradition in spatial economics that was advanced by state engineers who were trained at the Ecole des Ponts et ChaussΓ©es and worked for the State Corps engineers. Spurred in part by changes in power technology, especially the advent of the railroad, these engineers pioneered the spatial aspects of competition in a macroeconomic framework. The contribution of Jules Dupuit (1804 - 1866) and Emile Cheysson (1836 - 1910) are especially singled out for analysis, and are shown to have anticipated later important developments in spatial economic theory.
ARE ART AUCTION ESTIMATES BIASED?
ABSTRACT This paper considers whether pre-sale auction estimates are unbiased predictors of price when "no-sales" are considered utilizing a newly constructed sample of over 500 works by eight early 20 th century American artists. Unbiased pre-sale auction estimates in predicting price, while expected, are generally not supported in previous work, but these studies (excepting one) do not include no-sales in the calculations. In order to study the question we employ a standard approach that uses an inverse Mills ration arising from a sample selection probit, as suggested by We find that controlling for selection bias, pre-sale auction estimates appear to be biased downward and we offer possible reasons for this result
ARE ART AUCTION ESTIMATES BIASED? (forthcoming Southern Economic Journal: http://journal.southerneconomic.org/doi/abs
ABSTRACT This paper considers whether pre-sale auction estimates are unbiased predictors of price when "no-sales" are considered utilizing a newly constructed sample of over 500 works by eight early 20 th century American artists. Unbiased pre-sale auction estimates in predicting price, while expected, are generally not supported in previous work, but these studies (excepting one) do not include no-sales in the calculations. In order to study the question we employ a standard approach that uses an inverse Mills ration arising from a sample selection probit, as suggested by We find that controlling for selection bias, pre-sale auction estimates appear to be biased downward and we offer possible reasons for this result
Associations between cardiorespiratory fitness, physical activity and clustered cardiometabolic risk in children and adolescents: the HAPPY study
Clustering of cardiometabolic risk factors can occur during childhood and predisposes individuals to cardiometabolic disease. This study calculated clustered cardiometabolic risk in 100 children and adolescents aged 10-14Β years (59 girls) and explored differences according to cardiorespiratory fitness (CRF) levels and time spent at different physical activity (PA) intensities. CRF was determined using a maximal cycle ergometer test, and PA was assessed using accelerometry. A cardiometabolic risk score was computed as the sum of the standardised scores for waist circumference, blood pressure, total cholesterol/high-density lipoprotein ratio, triglycerides and glucose. Differences in clustered cardiometabolic risk between fit and unfit participants, according to previously proposed health-related threshold values, and between tertiles for PA subcomponents were assessed using ANCOVA. Clustered risk was significantly lower (pβ<β0.001) in the fit group (mean 1.21βΒ±β3.42) compared to the unfit group (mean -0.74βΒ±β2.22), while no differences existed between tertiles for any subcomponent of PA. Conclusion These findings suggest that CRF may have an important cardioprotective role in children and adolescents and highlights the importance of promoting CRF in youth
Cardiorespiratory fitness is associated with hard and light intensity physical activity but not time spent sedentary in 10β14 year old schoolchildren: the HAPPY study
Sedentary behaviour is a major risk factor for developing chronic diseases and is associated with low cardiorespiratory fitness in adults. It remains unclear how sedentary behaviour and different physical activity subcomponents are related to cardiorespiratory fitness in children. The purpose of this study was to assess how sedentary behaviour and different physical activity subcomponents are associated with 10β14 year-old schoolchildren's cardiorespiratory fitness
Physical activity, obesity and cardiometabolic risk factors in 9- to 10-year-old UK children of white European, South Asian and black African-Caribbean origin: the Child Heart And health Study in England (CHASE)
Physical inactivity is implicated in unfavourable patterns of obesity and cardiometabolic risk in childhood. However, few studies have quantified these associations using objective physical activity measurements in children from different ethnic groups. We examined these associations in UK children of South Asian, black African-Caribbean and white European origin. This was a cross-sectional study of 2,049 primary school children in three UK cities, who had standardised anthropometric measurements, provided fasting blood samples and wore activity monitors for up to 7 days. Data were analysed using multilevel linear regression and allowing for measurement error. Overall physical activity levels showed strong inverse graded associations with adiposity markers (particularly sum of skinfold thicknesses), fasting insulin, HOMA insulin resistance, triacylglycerol and C-reactive protein; for an increase of 100 counts of physical activity per min of registered time, levels of these factors were 12.2% (95% CI 10.2-14.1%), 10.2% (95% CI 7.5-12.8%), 10.2% (95% CI 7.5-12.8%), 5.8% (95% CI 4.0-7.5%) and 19.2% (95% CI 13.9-24.2%) lower, respectively. Similar increments in physical activity levels were associated with lower diastolic blood pressure (1.0 mmHg, 95% CI 0.6-1.5 mmHg) and LDL-cholesterol (0.04 mmol/l, 95% CI 0.01-0.07 mmol/l), and higher HDL-cholesterol (0.02 mmol/l, 95% CI 0.01-0.04 mmol/l). Moreover, associations were broadly similar in strength in all ethnic groups. All associations between physical activity and cardiometabolic risk factors were reduced (albeit variably) after adjustment for adiposity. Objectively measured physical activity correlates at least as well with obesity and cardiometabolic risk factors in South Asian and African-Caribbean children as in white European children, suggesting that efforts to increase activity levels in such groups would have equally beneficial effect
Effects of reallocating time in different activity intensities on health and fitness: a cross sectional study
BACKGROUND:
The effects of replacing time in specific activity categories for other categories (e.g. replacing sedentary time with light activity) on health and fitness are not well known. This study used isotemporal substitution to investigate the effects of substituting activity categories in an equal time exchange fashion on health and fitness in young people.
METHODS:
Participants were drawn from schools in Camden, London (nβ=β353, mean age 9.3βΒ±β2.3 years). Time sedentary, in light and in moderate-to-vigorous activity (MVPA) was measured via accelerometry. The effects of substituting time in activity categories (sedentary, light and MVPA) with equivalent time in another category on health and fitness were examined using isotemporal substitution.
RESULTS:
In single and partition models, MVPA was favourably associated with body fat %, horizontal jump distance and flexibility. Time sedentary and in light activity were not associated with health and fitness outcomes in these models. In substitution models, replacing one hour of sedentary time with MVPA was favourably associated with body fat % (Bβ=β-4.187; 95% confidence interval (CI), -7.233, -1.142), horizontal jump distance (Bβ=β16.093; 95% CI, 7.476, 24.710) and flexibility (Bβ=β4.783; 95% CI, 1.910, 7.656). Replacing time in light activity with MVPA induced similar benefits but there were null effects for replacing sedentary with light intensity.
CONCLUSION:
Substituting time sedentary and in light activity with MVPA was associated with favourable health and fitness. Time in sedentary behaviour may only be detrimental to health and fitness when it replaces time in MVPA in young people
- β¦