A researcher compares the effectiveness of two different instructional methods for teaching physiology. A sample of 189 students using Method 1 produces a testingaverage of 71.9. A sample of 141 students using Method 2 produces a testing average of 78.3. Assume the standard deviation is known to be 11.07 for Method 1 and11.9 for Method 2. Determine the 98 % confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2.Step 1 of 2: Find the critical value that should be used in constructing the confidence interval.AnswerHow to enter your answer (opens in new window)TablesKeypadKeyboard Shortcuts

The objective of this question is to determine the 98% confidence interval for the true difference…

Answered: A researcher compares the effectiveness…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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A study is run comparing HDL cholesterol levels between men who exercise regularly and those who do not. The 50 men who exercise regularly have a mean HDL of 48.5 with a standard deviation of 12.5. The 100 men who do not exercise regularly have a mean of 56.9 with a standard deviation of 11.9. Construct a 95% confidence interval for the difference between means, assuming equal variance. Give an interpretation of the confidence interval. You MUST show your work
Mrs. Gallas wanted to estimate the average weight of an Oreo cookie to determine if theaverage weight was less than advertised. She selected a random sample of 30 cookies andfound the weight of each cookie (in grams). The mean weight was = 11.1921 grams with astandard deviation of sx = 0.0817 grams. Make a 95% confidence interval to estimate the truemean weight of an Oreo. 1. What is the formula for calculating the standard deviation of the sampling distribution of x? 2.What condition must be met to use this formula? Has it been met?
A new drug is being tested to see if it reduces the frequency of migraines. Study participants were divided into two groups. 49 participants in group 1 received the medication; 42 participants in group 2 received a placebo. After a period of six months, group 1 had a mean of 4 migraines. It is known that the population standard deviation for this group is 1.3 migraines. Group 2 had a mean of 5.4 migraines. The population standard deviation for this group is 1.7 migraines. Can we conclude that the medication reduces the population mean number of migraines? Use αα =0.01. Note: If t-test, then unequal variances are assumed. Question a)Let: μ1μ1 = the population mean number of migraines with the medication μ2μ2 = the population mean number of migraines with the placebo (Step 1) State the null and alternative hypotheses by selecting the appropriate symbol, and identify which tailed test: H0:H0: μ1μ1 μ2μ2 H1:H1: μ1μ1 μ2μ2 Which tailed test…
#4data: 0.06, 0.11, 0.16, 0.15, 0.14, 0.08, 0.15. Use the sample data from #4 to construct a 98% confidence interval estimate for the standard deviation of the amount nitrogen-oxide emission for all cars.
A random sample of 34 chemists from Washington state shows an average salary of $41857, the population standard deviation for chemist salaries in Washington state is $697. A random sample of 35 chemists from Florida state shows an average salary of $44632, the population standard deviation for chemist salaries in Florida state is $900. A chemist that has worked in both states believes that chemists in Washington make a different amount than chemists in Florida. At a=0.05 is this chemist correct? Let Washington be sample 1 and Florida be sample 2. The correct hypotheses are: Ο Ηο: μι μ2(claim) Ο Ηο: μι 2 με HAM12(claim) Ho: M₁ = H2 1 HAM12(claim) Since the level of significance is 0.05 the critical value is 1.96 and -1.96 The test statistic is: (round to 3 places) The p-value is: (round to 3 places)
The design of controls and instruments affects how easily people can use them. A student project investigated this effect by asking 25 right handed students to turn a knob with their right hands that moved an indicator by screw action. There were two identical instruments, one with a right-hand thread and the other with a left-hand thread. The table given has the data from the student project.1. Calculate and interpret a 90% confidence interval for the mean time advantage of right hand over left hand threads in the setting above.
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We want to test whether the mean fluoride levels in water fountains is worse in A or B. In order to test, a sample of 49 different water samples was taken from A and a sample was taken from 36 samples in B. A has a sample average of 2.3 micrograms of fluroide per deciliter of water and B has a sample average of 1.4 micrograms per deciliter of water. Further, A has a known standard deviation A=1.5 and B has a known standard deviation B=1.7. Find the p-value for the following hypothesis test: H0: uA-uB=0 vs Ha: uA-uB>0.

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