Assignment: Read Chapter 23 Do exercises 1, 2, 5 Statistic for the day: Weight of the official disc used in ultimate: 175 grams Assignment: Read Chapter 23 Do exercises 1, 2, 5 These slides were created by Tom Hettmansperger and in some cases modified by David Hunter

Phone Women Men median 100 60 mean 150 91 SD 178 111 sample size 127 Research Hypothesis: In stat100, women spend more time on the phone than men. Women Men median 100 60 mean 150 91 SD 178 111 sample size 127 96 p-value (2-sided) .003 Conclusion: Support the research advocate. There is strong evidence that women spend more time on the phone than men on average.

Women Men median 100 60 mean 150 91 SD 178 111 sample size 127 96 SEM How to compute the p-value: Women Men median 100 60 mean 150 91 SD 178 111 sample size 127 96 SEM 15.8 11.4 SD of diff sqrt(15.82 + 11.42) = 19.5 Test Statistic = (150 – 91)/19.5 = 3.03 Look up 3.03 in normal table (3.00 is close) 1-sided p-value is 1 minus the entry, i.e. 1−.9987 = .0013 2-sided p-value is double the 1-sided p-value or .0026

Remember these steps! State the alternative and null hypotheses. Collect and summarize data and compute the test statistic. Find the p-value. Decide whether the data supports the alternative hypothesis. Research question: Do males and females in Stat 100 differ with respect to average __________? Variable Sex N Mean StDev SE Mean -------- ------ --- ------ ------ ------- Credits Female 136 15.566 2.073 0.178 Male 100 15.250 1.833 0.183 Fastcar Female 134 91.5 14.92 1.29 Male 98 108.4 23.88 2.41 Cigpacks Female 136 0.419 1.227 0.105 Male 101 1.108 2.300 0.229

Remember these steps! Yellow .14 Blue .24 Green .16 Brown .13 Red State the alternative and null hypotheses. Collect and summarize data and compute the test statistic. Find the p-value. Decide whether the data supports the alternative hypothesis. Research question: Do ______ M&M’s really occur in the proportion claimed on the M&M’s website? http://us.mms.com/us/about/products/milkchocolate/ Yellow .14 Blue .24 Green .16 Brown .13 Red Orange .20

Remember these steps! Color Claimed Count in sample Yellow .14 783 State the alternative and null hypotheses. Collect and summarize data and compute the test statistic. Find the p-value. Decide whether the data supports the alternative hypothesis. Research question: Do ______ M&M’s really occur in the proportion claimed on the M&M’s website? Color Claimed Count in sample Yellow .14 783 Blue .24 1280 Green .16 803 (Counts come from a representative sample of size 5533.)