REMINDER: Fill out your course evaluation by Sunday. Also, CAOS and SATS extended to Sunday, December 8 23:50.

Transcription

1 REMINDER: Fill out your course evaluation by Sunday. Also, CAOS and SATS extended to Sunday, December 8 23:50.

2 STA220 review session: Thursday December 5, 10:00 12:00, SS 2110 For more information:

3 A few highlights from the Final exam information page on Coursera: The exam consists of 35 multiple choice questions. Answers must be marked with pencil on a Scantron answer sheet. There are no penalties (negative marks) for wrong answers. The first 5 questions are each worth 2 marks and a blank response receives 0.4 marks for these questions. The remaining 30 questions are each worth 3 marks and a blank response receives 0.6 marks for these question. Practice Exams: There is a currently a link to online multiple choice practice problems. A practice exam (with R output) will be posted tomorrow morning. You should bring: A two sided, 8.5 by 11 inch, handwritten aid sheet, A calculator, Pencils and erasers for completing the Scantron answer sheet, Your University of Toronto student card. Extra office hours: The TAs will be holding lots of office hours leading up to the exam. The schedule is posted on the TA office hours page. Coverage: The exam covers the entire course. See the Content by Week page.

4 New optional videos posted:

5 A concept done poorly on CAOS: Suppose that it has been established that the mean body temperature of healthy adults is 37 degrees Celsius with a standard deviation of 0.5 degrees Celsius. I think the mean temperature is lower for university students. So I take a random sample of 100 students from my population, which is all students at the University of Toronto, and I found that the mean is 36.8 degrees Celsius. Which of the following is the most appropriate statistical conclusion? A. I cannot conclude that the mean body temperature for UofT students is less than 37 degrees because 36.8 degrees is less than one standard deviation from 37 degrees. B. I can conclude that UofT students have a lower mean body temperature because I have a simple random sample with a reasonably large sample size. C. I can conclude that UofT students have a lower mean body temperature because the difference between 37 and 36.8 degrees is much larger than the standard error.

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7 A concept done poorly on CAOS: Suppose that a random sample of 60 resulted in a 90% confidence interval for the proportion of female students at the University of Toronto who have been vaccinated for HPV of (0.52, 0.76). How many of the following are correct interpretations of the confidence interval? A. We would expect 90% of all possible sample proportions from this population to be between 0.52 and B. 90% of the time the population proportion will be between 0.52 and C. The method used to construct the interval will produce an interval that includes the value of the population proportion about 90% of the time in repeated sampling. D. If 100 different random samples of size 60 from this population were each used to construct a 90% confidence interval, 90 of them will contain the value of the population proportion. E. The probability that the population proportion is between 0.52 and 0.76 is 0.90.

8 A concept done poorly on CAOS:

9 If there s no bias In sampling, the probability that subjects with a characteristic are chosen is the proportion of subjects in the population. In experiments, subjects with a characteristic are just as likely to be in one treatment group as another. So any differences among the treatment groups are just due to chance. (Ideally, the subjects in one treatment group have the same characteristics as subjects in the other treatment group.) How could you get more accuracy in your estimates? Does having only a sample, randomly chosen, from a population affect my ability to generalize to the population?

10 A concept done poorly on CAOS: What is extrapolation and why is it a problem in regression?