American communities experience an average of 1026 violent crimes per year. A criminologist wonders whether adding 10% more uniformed patrol personnel would result in a significant reduction in violent crimes. She obtains a federal grant and obtains a stratified national sample of 20 communities. She uses the funds to increase the uniformed patrol personnel by 10% . Her data are presented below: Sample Mean: 876 Sample Standard Deviation: 328 a) Test her hypothesis that adding 10% more uniformed patrol personnel will result in a reduction in violent crimes. b) What conclusions could be drawn from these results?
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Step 1
- Null Hypothesis (H0): Adding 10% more uniformed patrol personnel will not result in a reduction in violent crimes (μ = 1026). - Alternative Hypothesis (H1): Adding 10% more uniformed patrol personnel will result in a reduction in violent crimes (μ < 1026). Show more…
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