HW_Hyp_Tests_Part2_Solutions

# There is sufficient evidence at the 005 significance

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Unformatted text preview: ll enough to be considered unusual. Which one is your conclusion “in context” (Click in the box next to your choice): “There is not sufficient evidence at the 0.05 significance level to support the claim that the new diet increases the birth weights of newborns.” “There is sufficient evidence at the 0.05 significance level to support the claim that the new diet increases the birth weights of newborns.” b) If you are wrong about this conclusion, what type of error would it be? This would be a Type I Error. So we concluded that this new diet for expecting mothers will increase the birth weight of their babies, when it actually doesn't. This is a False Alarm. c) Find a 90% confidence interval for the mean birth weight for all babies whose mother follows the new diet. The name of the TI-83/84 calculator function you will be using: TInterval State your answer in words: We are 90% confident that the population mean birth weight for ALL babies whose mother follows the new diet will be between 7.5345 and 8.1055 pounds. So notice that the hypothesized population mean of 7.53 is NOT in this interval, so it agrees with our Hypothesis Test. But also note how close it was to being in the interval. d) How large of a sample size would you need in order to have a confidence level of 95% and a margin of error of E = 0.10 pound? Use σ ≈ 1.14 pounds. Be sure to show how your answer was calculated: n = (z*sigma/E)^2 = ( 1.9600 * 1.14 / 0.10 ) ^ 2 = 499.25 and we Round UP to: n = 500 ================================= 4) According to the Centers for Disease Control, 56% of all tuberculosis cases in 1999 were of foreign-born residents of the United States. A researcher believes that this proportion has changed from its 1999 level. She obtains a random sample of 300 tuberculosis cases in the United States and determines that 180 of them are foreign-born. a) Is there sufficient evidence to support the claim that the proportion of all cases of tuberculosis that are from foreign-born residents has changed at the α =0.05 significance level? Page 7 of 9 Null Hyp...
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## This note was uploaded on 11/21/2013 for the course MTH 243 taught by Professor Dr.kim during the Winter '08 term at Southern Oregon.

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