女朋友的生统老师出了一题不知所云的考题 看了很久也看不懂，附上题目与解答 希望有神人帮帮忙解释一下 A researcher wanted to study the effects of mentoring on intelligence scores. He wanted to know as a baseline what the average intelligence of his students were relative to the general population. He used a standardized IQ test which has a mean of 100 and standard deviation of 16. The 50 students in his study scored an average of 102 on the IQ test. At what percentile of intelligences is the average IQ of his students relative to his population ? 1. First find the standard error of the mean for a sample size of 50 ，16/SQRT(50) = 2.26 2. How many standard errors are there between the observed sample mean and the population mean: (102-100)/2.26 = .8849 standard errors. 3. The percent of area under the normal curve from negative infinity to .8849 =81.2%, meaning the average intelligence of this set of students is higher than 81.2% of all other samples of 50 students. It is also 31.2% above an average IQ given this sample size. Finally, we can use the 1-sample z-test to test hypotheses. The general framework of Hypothesis testing will be covered in future lessons. _____________________________________________________________________ 比较大的问题是我看不懂 At what percentile of intelligences is the average IQ of his students relative to his population ? 这句的意思看不太懂 解答中的第三点也看不出它想表达出的意思。81.2%的学生高於其他的学生? 这实在不懂阿 ※ 编辑: siaxing 来自: 114.27.134.195 (04/17 17:59)