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In: Statistics and Probability

7. Suppose a researcher wishes to discern if there is a significant difference in the running...

7. Suppose a researcher wishes to discern if there is a significant difference in the running times of two computer programs. He performs a hypothesis test with the null hypothesis being that there is no difference in their average running times, and the alternative hypothesis being that there is a difference. The signficance level is set at α =0.05. The first program was run n1 = 5 times with an average running time of ¯ x1 = 53.72 seconds and a sample standard deviation of s1 = 11.72 seconds. The second program was run n2 = 6 times with an average running time of ¯ x2 =60.64 seconds and a sample standard deviation of s2 =8.21 seconds. What conclusion should the researcher reach? Hints: You may estimate the difference of means as a t-distribution with 4 degrees of freedom. You may use the following formula for the standard error
SE¯ x2−¯ x1 =ss2 1 n1
+ s2 2 n2

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orchestra answered 2 years ago
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