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Conducting statistics for herbal remedies

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Although there is a popular belief that herbal remedies such as ginkgo biloba and ginseng may improve learning and memory in healthy adults, these effects are usually not supported by well-controlled research. In a typical study, a researcher obtains a sample of n=36 participants and has each person take the herbal supplements every day for 90days. At the end of the 90 days, each person takes a standardized memory test. For the general population, scores fromt he test are normally distributed with a mean of 80 and a standard deviation of 18. The sample research participants had an average of M=84.

a-assuming a two-tailed test, state the null hypothesis in a sentence that includes the two variables being examined.

b-using symbols, state the hypothese (Ho and H1)for the two-tailed test.

c-sketch the appropriate distribution, and locate the critical region for alpha=.05

d-calculate the test statistic (z-score) for the sample.

e-what decision should be made about the null hypothesis, and what decision should be made about the effect of the herbal supplements.

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The expert conducts statistics for herbal remedies. The two-tailed test, and null hypothesis for two variables being examined is examined.

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Although there is a popular belief that herbal remedies such as ginkgo biloba and ginseng may improve learning and memory in healthy adults, these effects are usually not supported by well-controlled research. In a typical study, a ...

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  • BSc , Wuhan Univ. China
  • MA, Shandong Univ.
Recent Feedback
  • "Your solution, looks excellent. I recognize things from previous chapters. I have seen the standard deviation formula you used to get 5.154. I do understand the Central Limit Theorem needs the sample size (n) to be greater than 30, we have 100. I do understand the sample mean(s) of the population will follow a normal distribution, and that CLT states the sample mean of population is the population (mean), we have 143.74. But when and WHY do we use the standard deviation formula where you got 5.154. WHEN & Why use standard deviation of the sample mean. I don't understand, why don't we simply use the "100" I understand that standard deviation is the square root of variance. I do understand that the variance is the square of the differences of each sample data value minus the mean. But somehow, why not use 100, why use standard deviation of sample mean? Please help explain."
  • "excellent work"
  • "Thank you so much for all of your help!!! I will be posting another assignment. Please let me know (once posted), if the credits I'm offering is enough or you ! Thanks again!"
  • "Thank you"
  • "Thank you very much for your valuable time and assistance!"
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