生命科技的全球观察

生物技术体系的改变，生物药的生产制造，个性化用药、预防医学等将共同形成研发的新驱动力。     

YY英语求助站（1）

同学们,本期开始,"YY英语救助站"将热忱地为大家提供优质有效的服务!欢迎大家给我们"输送病号"(来信来稿)。我们将尽量解决你们在英语学习中遇到的"疑难杂症"!嘿嘿,YY两字要发字母Y的音,不要念错喽!至于为什么起这个名字,一方面,它同why(为什么)是谐音,另一方面,它们也是"语言"两字的拼音首字母。两者同时表示这是一个专门为语言学习排忧解难的场所哦!     

Introduction to Sample Size Choice for Confidence Intervals Based on t Statistics

Sample size can be chosen to achieve a specified width in a confidence interval. The probability of obtaining a narrow width given that the confidence interval includes the population parameter is defined as the power of the confidence interval, a concept unfamiliar to many practitioners. This article shows how to utilize the Statistical Analysis System (SAS) proc power procedure to determine an appropriate sample size and achieve sufficient power for a specified confidence interval. Two examples in sport and exercise science are used to illustrate sample size determination for confidence intervals in the dependent and independent t tests. The relevant SAS code and output are provided with detailed annotations. As the use of confidence intervals becomes a more integral part of studies in sport and exercise science, the reporting and analysis of their power should be considered much like that of hypothesis tests.     

Game location and aggression in rugby league

The present study examined the relationship between aggression and game location in rugby league. We videotaped a random sample of 21 professional rugby league games played in the 2000 Super League season. Trained observers recorded the frequency of aggressive behaviours. Consistent with previous research, which used territoriality theories as a basis for prediction, we hypothesized that the home team would behave more aggressively than the away team. The results showed no significant difference in the frequency of aggressive behaviours exhibited by the home and away teams. However, the away teams engaged in substantially more aggressive behaviours in games they lost compared with games they won. No significant differences in the pattern of aggressive behaviours for home and away teams emerged as a function of game time (i.e. first or second half) or game situation (i.e. when teams were winning, losing or drawing). The findings suggest that while home and away teams do not display different levels of aggression, the cost of behaving aggressively (in terms of game outcome) may be greater for the away team.