Introducing Statistics: Why Be Normal Practice Test

Because normal models are required whenever the sample size is greater than 30, even if the data are strongly skewed

Because a normal model can approximate a unimodal, roughly symmetric distribution and summarizes it well using mean and standard deviation

Because standardized tests always produce data that are exactly normal in every sample

Because assuming a normal model means the scores are caused by a normal distribution in each student’s brain

Because a normal model eliminates the possibility of unusually low or high scores