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This study quantified technical efficiency and the determinants of observed technical inefficiency of sawmills in Nigeria. A two-stage sampling technique was used to select 170 sawmillers in Ondo and Osun states, while questionnaire was used to obtain data from them between October and December 2003. The stochastic frontier approach was used to estimate technical efficiency of both small- and medium-scale sawmills, while the ordinary least square (OLS) regression analysis was used to estimate the determinants of the observed technical inefficiency. Empirical results indicate that medium-scale sawmillers are more efficient than their small-scale counterparts. However, both groups of sawmillers in Nigeria have potentials to expand their output. 相似文献
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BINGE DRINKING IN COLLEGE: THE IMPACT OF PRICE, AVAILABILITY, AND ALCOHOL CONTROL POLICIES 总被引:3,自引:0,他引:3
This paper estimates the effects of beer prices, alcohol availability, and policies related to driving under the influence of alcohol on drinking and binge drinking among youths and young adults. Data are from a nationally representative survey of students in U.S. colleges and universities. Separate estimates are obtained for underage male and female students, as well as for older male and female students. The estimates indicate that the drinking practices of male college students are generally insensitive to the price of beer. However, underage drinking and binge drinking by female students do respond significantly to price, although both are relatively inelastic. The results also show that strong drunk driving policies targeting youths and young adults significantly reduce drinking and binge drinking by male students. Similarly, these policies reduce drinking among female college students but appear to have little impact on their binge drinking. Instead, the results indicate that many elements of campus life (including participation in a fraternity or sorority, living on campus, and the ready availability of alcoholic beverages) are among the most important determinants of drinking and binge drinking among college students. 相似文献
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