In 2007, a study of close to 250,000 18-19 year-old Norwegian males found that first-borns have an IQ that is 2.3 points higher than those who are second-born. To see if you can find a similar evidence at your university, you collect data from 250 students, of which 140 are first-borns. After subjecting each of these individuals to an IQ test, you find that the first-borns score 108.3 with a standard deviation of 13.2, while the second borns achieve 107.1 with a standard deviation of 11.6. You hypothesize that first-borns and second-borns in a university population have identical IQs against the one-sided alternative hypothesis that first borns have higher IQs. Using a size of the test of 5%, what is your conclusion?

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The Answer of In 2007, a study of close to 250,000 18-19 year-old Norwegian males found that first-borns have an IQ that is 2.3 points higher than those who are second-born. To see if you can find a similar evidence at your university, you collect data from 250 students, of which 140 are first-borns. After subjecting each of these individuals to an IQ test, you find that the first-borns score 108.3 with a standard deviation of 13.2, while the second borns achieve 107.1 with a standard deviation of 11.6. You hypothesize that first-borns and second-borns in a university population have identical IQs against the one-sided alternative hypothesis that first borns have higher IQs. Using a size of the test of 5%, what is your conclusion?

In 2007, a Study of Close to 250,000 18-19 Year-Old