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In: Statistics and Probability
Some researchers claim that herbal supplements improve human memory. To test this claim, a researcher selects...
Some researchers claim that herbal supplements improve human memory. To test this claim, a researcher selects a sample of n = 25 college students. Each student is given herbal supplements daily for 6 weeks and then all the participants are given a standardized memory test. For the population, scores on the tests are normally distributed with µ = 70 and σ= 20. The sample of n = 25 students had a mean score of M = 80. Can we conclude that the memory scores of the sample after the “herbal supplement” treatment are significantly greater than those of the general population(population mean before treatment)? Perform a hypothesis test using a z- score statistic. Use a one-tailed test with α = .05.
The z-score statistic is
Solutions
Expert Solution
The z scare statistics is 2.50
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