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Unformatted text preview: number of traffic accidents? You must use excel test functions. Solution. Null hypothesis H0: the modification didnt reduce the number of traffic accidents Alternative hypothesis H1: the modification reduced the number of traffic accidents Use Excel, we get t-Test: Paired Two Sample for Means Variable 1 Variable 2 Mean 7.125 4.625 Variance 4.125 7.982143 Observations 8 8 Pearson Correlation 0.308088 Hypothesized Mean Difference df 7 t Stat 2.415229 P(T<=t) one-tail 0.023208 t Critical one-tail 1.894579 P(T<=t) two-tail 0.046416 t Critical two-tail 2.364624 From the above table, we know that the p-value is 0.023208 which is greater than alpha=0.01 So, we fail to reject the null hypothesis H0. We conclude that the modification didnt reduce the number of traffic accidents. Note: This is a paired test for two population means....
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This note was uploaded on 11/11/2011 for the course EC 315 taught by Professor Barcus during the Spring '10 term at Park.
- Spring '10