X correct incorrect ii with 99 confidence it can be

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___ X ___ Correct _______ Incorrect ii. With 99% confidence, it can be suggested that on average, in the population of all words, the words in Spanish are between 1.7427 characters shorter and 0.1627 characters longer than their corresponding equivalents in Russian. ___ X ___ Correct _______ Incorrect iii. The probability that the population mean difference in the number of characters between words in Spanish and their corresponding equivalents in Russian (Spanish – Russian) for the population of all words is between -1.7427 and 0.1627 characters is 0 or 1. ___ X ___ Correct _______ Incorrect alternative hypothesis: true difference in means is not equal to 0 99 percent confidence interval: -1.7427 0.1627 sample estimates: mean of the differences -0.79 mean sd se(mean) Spanish 7.32 2.1736 0.21736 Russian 8.11 3.5388 0.35388 Difference -0.79 3.627323 0.36273 100 n 100 100
3. Yellow (Maize) Car? ~ A loyal Michigan fan currently has a blue car. He plans to purchase a brand-new car and is considering a yellow car. He wonders if purchasing a brand-new yellow car will hurt his ability to sell the car in the future, say in three years. He decides to do some research about the average number of days it takes to sell a three-year-old yellow car. The stated average number of days it takes to sell a three-year-old car of any color is 30 days. He obtains a random sample of 40 yellow three-year-old cars up for sale and records the number of days it takes to sell each car. He would like to use these results to assess if yellow cars take longer to sell on average compared to that for three-year-old cars of any color, at the 5% level of significance. a. This loyal Michigan fan expressed the hypotheses for the test as shown:
[2] Briefly explain why these are not the correct hypotheses to be tested?
b. Suppose the average number of days it takes to sell a three-year-old yellow car really is 30 days. If we were to repeat this study 60 times, each time taking a random sample of 40 yellow three-year-old cars up for sale and conducting the same appropriate hypothesis test at the same significance level, then how many decisions would we expect to be incorrect?
Stats 250 Fall 2017 Exam 2 Page 4 of 8

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