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)
Math question: Differentiate y = 3sin(x)cos(x) + 2tan(x) + 5sec(x) up to 200 characters long.
+
What are the roots, vertex, and end behavior of the cubic function f(x) = x^3?
+
Question: Solve the equation for x: 2x + 5 = 17.
+
New questions in Mathematics
Solution of the equation y&#39;&#39; - y&#39; -6y = 0
Let the vectors be u=(-1,0,2) , v=(0,2,-3) , w=(2,2,3) Calculate the following expressions a)<u,w> b) &lt;2u- 5v,3w&gt;
A circle with a 12-inch diameter is folded in half and then folded in half again. What is the area of the resulting shape?
two particles start at the origin and move along the x axis. for 0 <= t <= 10, their respective position functions are given by x1 = cos(t) and x2 = (e^-3t) + 1. for how many values of t do the particles have the same velocity?
You have been hired to estimate the average weight of quarters in circulation. Based on the sample of quarters you collect (below), create a 90% confidence interval for the weight of quarters in circulation. Quarter Weights (grams) 5.631 5.714 5.719 5.689 5.551 5.723 5.705 5.627 5.627 5.715 5.576 5.632 5.641 5.676 5.660 5.699 5.609 5.634 5.713 5.591 5.674 5.675 5.684 5.694 5.655 5.632 5.598 5.675 5.628 5.562 5.636 5.583 5.567 5.551 5.649 5.708 5.696 5.614 5.637 5.601 5.628 5.711 5.566 5.653 5.653 5.597 5.687 5.717 5.678 5.654 5.556 5.707 5.563 5.628 5.679 5.714 5.555 5.719 5.634 5.647 5.717 5.612 5.705 5.657 5.670 5.607 5.687 5.666 5.612 5.718 5.714 5.713 5.663 5.641 5.589 5.656 5.712 5.639 5.577 5.580 5.674 5.636 5.625 5.597 5.616 5.591 5.616 5.700 5.706 5.695 5.562 5.699 5.607 5.573 5.659 5.632 5.654 5.568 5.628 5.687 5.605 5.689 5.687 5.554 5.618 5.701 5.681 5.645 5.714 5.665 5.661 5.634 5.714 5.586 5.656 5.673 5.657 5.717 5.611 5.578 5.579 5.614 5.644 5.724 5.647 5.566 5.697 5.558 5.586 5.586 5.611 5.573 5.573 5.709 5.629 5.649 5.552 5.615 5.645 5.611 5.686 5.588 5.641 5.704 5.703 5.696 5.557 5.551 5.725 5.608 5.725 5.603 5.677 5.638 5.573 5.640 5.561 5.631 5.563 5.671 5.662 5.569 5.648 5.680 5.681 5.551 5.555 5.578 5.701 5.645 5.670 5.574 5.594 5.705 5.633 5.719 5.680 5.647 5.641 5.553 5.616 5.698 5.552 5.566 5.559 5.697 5.686 5.560 5.629 5.701 5.622 5.615 5.553 5.608 5.637 5.663 5.696 5.714 5.675 5.613 5.594 5.669 5.569 5.716 5.705 5.603 5.709 5.717 5.606 5.581 5.575 5.601 5.600 5.664 5.715 5.705 5.583 5.586 5.592 5.550 5.628 5.662 5.603 5.559 5.676 5.558 5.678 5.671 5.642 5.581 5.568 5.706 5.665 5.712 5.574 5.602 5.699 5.716 5.693 5.711 5.635 5.612 BLANK #1: Is this a question involving mean or proportion? ***ANSWER "MEAN" OR "PROPORTION" (WITHOUT THE QUOTATION MARKS)*** BLANK #2: What is the LOW end of the estimate ***ANSWER TO 3 DECIMALS*** BLANK #3: What is the HIGH end of the estimate ***ANSWER TO 3 DECIMALS***
Estimate the fifth term if the first term is 8 and the common ratio is -1/2
4. Show that if n is any integer, then n^2 3n 5 is an odd integer
Substitute a=2 and b=-3 and c=-4 to evaluate 2ac/(-2b^2-a)
12(3+7)-5
3+7
The question is using rule 72 determine Kari wants to save 10,000 for a down payment on a house. Illustrate the difference in years it will take her to double her current 5,000 savings based on 6%, 12% and 18% interest rate .
3%2B2
Show work on 4108 divided by 4
(6Β²-14)Γ·11β€’(-3)
On Tuesday Shanice bought five hats.On Wednesday half of all the hats that she had were destroyed.On Thursday there were only 17 left.How many Did she have on Monday.
Let G be the center of gravity of triangle ABC. We draw through A a parallel to BC on which we take a point D so that DGβŠ₯BG. If the area of the quadrilateral AGBD is equal to s, show that ACΒ·BDβ‰₯2Β·s.
The average weekly earnings in the leisure and hospitality industry group for a re‐ cent year was $273. A random sample of 40 workers showed weekly average ear‐ nings of $285 with the population standard deviation equal to 58. At the 0.05 level of significance can it be concluded that the mean differs from $273? Find a 95% con‐ fidence interval for the weekly earnings and show that it supports the results of the hypothesis test.
2 - 6x = -16x + 28
1. The cost to transport 250 packages of cement 120 kilometers is $600. What will be the cost to transport 500 packages 300 kilometers?
A membership to the gym cost $25 per person in 1995. The membership cost has increased by an average $6 per person for each year since 1995. Write a linear equation for the cost of a gym membership for one person since 1995. What is the cost of a gym membership in 2009?