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)
What values of the coefficient "a" will result in vertically stretched parabolas when graphing the function 𝑦 = ax^2?
+
Find the amplitude, period, asymptotes, and domain of the function f(x) = cot(x).
+
What is the length of the hypotenuse if the adjacent side measures 5 and the angle of elevation is 30 degrees?
+
New questions in Mathematics
A=m/2-t isolate t
-442/c+5=26 what is c?
If L (-2, -5) reflected across y = -4. What are the coordinates of L?
132133333-33
The data set (75, 85, 58, 72, 70, 75) is a random sample from the normal distribution No(µ, σ). Determine a 95% two-sided confidence interval for the mean µ .
Director of reservations believes that 9% of the ticketed passengers are no-shows. If the directors right what is the probability that the proportion of no-shows in a sample of 789 ticketed passengers with differ from the population proportion buy more than 3% round your answer to four decimal places.
Suppose a large shipment of cell phones contain 21% defective. If the sample of size 204 is selected, what is the probability that the sample proportion will differ from the population proportion by less than 4% round your answer to four decimal places
2x-4y=-6; -4y+4y=-8
Raúl, Gilberto and Arturo are playing golf; The probabilities of winning for each one are as follows: (Raúl wins) = 20% (Gilberto wins) = 0.05% (Arturo wins) = ¾%. Perform operations and order events from least to most probable.
7=-4/3y -1
Use the sample data and confidence level given below to complete parts​ (a) through​ (d). A drug is used to help prevent blood clots in certain patients. In clinical​ trials, among 4336 patients treated with the​ drug, 194 developed the adverse reaction of nausea. Construct a ​99% confidence interval for the proportion of adverse reactions.
TEST 123123+1236ttttt
4+168×10³×d1+36×10³×d2=-12 -10+36×10³×d1+72×10³×d2=0
Determine the increase of the function y=4x−5 when the argument changes from x1=2 to x2=3
Solve equations by equalization method X-8=-2y 2x+y=7
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
A hardware bill totals $857.63 with discounts of 5% and 3%. What is the net cost of the Material ?
Two particles of electrical charges Q1=3.8×10-⁶C and q,=4.4×10-⁶C are separated in vacuum by a distance of 4.0.10-⁸ m. Since K=9.0.10⁹ N.m²/C², the intensity of the interaction force between them, in newtons, is?
What is the total amount due and the amount of interest on a 3-year loan of $1,000 at a simple interest rate of 12% per year?
Solve the following 9x - 9 - 6x = 5 + 8x - 9