Question

Researchers conducted an experiment to test the effects of alcohol. Errors were recorded in a test of visual and motor skills for a treatment group of 27 people who drank ethanol and another group of 21 people given a placebo. The errors for the treatment group have a standard deviation of 0.98​, and the errors for the placebo group have a standard deviation of 0.85. Use a 0.01 significance level to test the claim that the treatment group has errors that vary significantly more than the errors of the placebo group. Assume that the two populations are normally distributed. Sample 1: treatment group, n1 = 27, s1 = 0.98. Sample 2: placebo group: n2 = 21, s2 = 0.85

102

likes
508 views

Answer to a math question Researchers conducted an experiment to test the effects of alcohol. Errors were recorded in a test of visual and motor skills for a treatment group of 27 people who drank ethanol and another group of 21 people given a placebo. The errors for the treatment group have a standard deviation of 0.98​, and the errors for the placebo group have a standard deviation of 0.85. Use a 0.01 significance level to test the claim that the treatment group has errors that vary significantly more than the errors of the placebo group. Assume that the two populations are normally distributed. Sample 1: treatment group, n1 = 27, s1 = 0.98. Sample 2: placebo group: n2 = 21, s2 = 0.85

Expert avatar
Jon
4.6
110 Answers
1. Hypotheses:

- Null hypothesis H_0: \sigma_1^2 = \sigma_2^2

- Alternative hypothesis H_a: \sigma_1^2 > \sigma_2^2

2. Test Statistic:

- Calculated F-statistic: F = \frac{s_1^2}{s_2^2} = 1.329

3. Critical Value:

- From F-distribution table at \alpha = 0.01, with df_1 = 26 and df_2 = 20: 2.829

4. Decision Rule:

- If F > 2.829, reject H_0.

- Else, do not reject H_0.

5. Conclusion:

- Since 1.329 < 2.829, do not reject H_0.

- Therefore, no sufficient evidence to support that the treatment group has more variability.

Frequently asked questions (FAQs)
Q: What is the period of a sine function with a coefficient of 3 in front of the angle measurement?
+
Math Question: What is the value of f(x) = 3x² + 5x + 2, where x = 2?
+
What is the median of a set with an odd number of values, given that the values are 4, 8, 12, and 18?
+
New questions in Mathematics
11(4x-9)= -319
5/8 x 64
What is the amount of interest of 75,000 at 3.45% per year, at the end of 12 years and 6 months?
Use the elimination to find the solution to each linear system. X+y=43 2x-y=20
a bank finds that the balances in its savings accounts are normally distributed with a mean of $500 and a standard deviation off of $40. What is the probability that a randomly selected account has a balance of more than $400?
4.2x10^_6 convert to standard notation
4x567
Suppose 56% of politicians are lawyers if a random sample of size 873 is selected, what is the probability that the proportion of politicians who are lawyers will be less than 55% round your answer to four decimal places
how many arrangements can be made of 4 letters chosen from the letters of the world ABSOLUTE in which the S and U appear together
Use the power rule for logarithms to solve the following word problem exactly. If you invest $1, 000 at 5% interest compounded annually, how many years will it take before you have $2,000?
A machine produces 255 bolts in 24 minutes. At the same rate, how many bolts would be produced in 40 minutes?
-1%2F2x-4%3D18
Show work on 4108 divided by 4
Determine a general formula​ (or formulas) for the solution to the following equation.​ Then, determine the specific solutions​ (if any) on the interval [0,2π). cos30=0
-5x=115
Consider mixing 150 ml, 0.1M, HCI with 100 ml, 0.2M, KOH solution. Determine the pH of final solution.
The blood types of individuals in society are as follows: A: 30%, B: 25%, AB: 20%, 0: 25%. It is known that the rates of contracting a certain disease according to blood groups are as follows: A: 7%, B: 6%, AB: 7%, 0: 4%. Accordingly, if a person selected by chance is known to have this disease, what is the probability of having blood group O?
The slope of the tangent line to the curve f(x)=4tan x at the point (π/4,4)
calculate the product of 4 and 1/8
A gas is leaking at 3.5ft3/min in a room of 2.9m by 6.9ft by 15.7m. How long would it take (in seconds) for 22% of the room to reach the LFL, if the gas has a LFL of 2.51%?