The first, a hypothesis test involving a single mean, is exemplified by another question about sardines. (There are not many exciting examples that illustrate this type of test.). The second type of hypothesis test is much more interesting and it involves the difference between two means (we call this a “difference in means” test.). You have been calculating differences in means using the health survey data; in this quiz, you will carry out a difference-in-means test using data on bicycle trip duration.
*** Note: All the questions, except the last one, are answerable using pen and paper. Indeed, you will come away from this class with a much better understanding of the concepts if you try to work through them “by hand” rather than first going to the computer or calculator. Thus, in addition to answering the quiz, you are required to send to me your written answers. You may scan you answers and email to me a pdf or type up your answers in Word and email it to me. You must turn in individual, NOT group, writeups, and cases of clear copying will be considered cheating and given a final score of 0.
1. True or False. In statistics, the result that in large enough samples, the mean of a random variable is normally distributed, regardless of how the random variable is distributed, is called the Central Limit Theorem
2.You observe five random numbers: 2,2,3,4,4. The mean of this data is 3. What is the standard deviation? (This should be done with a pen and paper, and the formula on p. 36, note 16 of
