To simplify decisionmaking a university changes its admissio

To simplify decision-making, a university changes its admissions policy one year from a holistic approach (i.e. considering many factors, such as SAT scores, GPA, extracurricular involvement, etc.) to a simple SAT cutoff rule. One fear of doing this is that when ability is measured less precisely it may vary more among incoming students. To test this possibility, the university administers an aptitude test to 41 students chosen randomly from the year before the policy change and to 61 students from the year after the change. The resulting sample variance increases from between policy regimes. Provide a 95% (two-sided) confidence interval for the percentage increase of ox the variance in test scores between policy regimes. Is there sufficient evidence to conclude that the variance of ability increased with the policy change? Test at the alpha = .05 level. Is there sufficient evidence to conclude that the variance of ability increased by at least 25% with the policy change? Test at the alpha = .05 level.

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