1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kipiarov [429]
3 years ago
12

A study was conducted to determine whether magnets were effective in treating pain. The values represent measurements of pain us

ing the visual analog scale. Assume that both samples are independent simple random samples from populations having normal distributions. Use a 0.05 significance level to test the claim that those given a sham treatment have pain reductions that vary more than the pain reductions for those treated with magnets.
n xbar s
Sham 20 0.41 1.26
Magnet 20 0.46 0.93
Mathematics
1 answer:
Zanzabum3 years ago
3 0

Answer:

Step-by-step explanation:

Hello!

The objective of the study is to determine whether the magnets are effective in treating pain. For these two independent groups of individuals with equal affections were randomly sampled, one was treated with magnets and the other group of individuals, call it control group, was treated with a placebo treatment.

The information for both samples is:

X₁: pain measurement using a visual analog scale after the individual received magnet treatments.

X₁~N(μ₁;σ₁²)

n₁= 20

X[bar]₁= 0.46

S₁= 0.93

X₂: pain measurement using a visual analog scale of an individual of the control groups.

X₂~N(μ₂;σ₂²)

n₂= 20

X[bar]₂= 0.41

S₂= 1.26

The claim is that the pain reductions of the control group have more variation than the pain reductions of the target group. If it's so then we could suspect that the population variance of the control group, σ₂², will be greater than the population variance of the magnet group, σ₁².

To test the relationship between these two population variances you have to conduct a variance ratio test using the Snedecors F statistic.

The hypotheses are:

H₀: σ₂² ≤ σ₁²

H₁: σ₂² > σ₁²

α: 0.05

F= (\frac{S_2^2}{S_1^2}) * (\frac{Sigma_2^2}{Sigma_1^2} )~~ F_{(n_2-1);(n_1-1)}

This hypothesis test is one-tailed to the right, there is only one critical value:

F_{(n_2-1);(n_1-1); 1 - \alpha } = F_{19;19; 0.95}= 2.17

The decision rule for the test is:

If F_{H_0} ≥ 2.17, then the decision is to reject the null hypothesis.

If F_{H_0} < 2.17, then the decision is to not reject the null hypothesis.

F_{H_0}= \frac{S_2^2}{S_1^2}*\frac{Sigma_2^2}{Sigma_1^2}  = \frac{(1.26)^2}{(0.93)^2} * 1

F_{H_0} = 1.835 = 1.84

Since the calculated value of F is less than the critical value, the decision is to reject the null hypothesis. So using a 5% significance level the decision is to not reject the null hypothesis, you can conclude that the population variance of the pain reduction of the control group is less or equal than the population variance of the pain reduction on individuals treated with magnets.

I hope it helps!

You might be interested in
What is the exponent for 9x9x9x9? help plz
Alenkinab [10]

Answer:

9^4

Step-by-step explanation:

There is 4 nines.

9*9*9*9 = 6561

9^4 = 6561

9^3 = 729

5 0
3 years ago
A triangle has sides measuring 2 inches and 7 inches. If x represents the
xz_007 [3.2K]

Answer:

its d.

Step-by-step explanation:

the other guy is wrong

3 0
3 years ago
What is the answer to the problem (m-3)(-10)
OverLord2011 [107]

The answer is -10m + 30




8 0
3 years ago
i beg of yall a crown, 5 stars, a heart and a ty comment to answer my questions iv posted on my profile, ill be posting more too
Over [174]

Answer:

I would say the answer is $5.00/lb

Have a wonderful day!

6 0
2 years ago
I need help with my math homework x+23=9/10
BartSMP [9]

Answer:

-221/10

Step-by-step explanation:

In the attached file

8 0
3 years ago
Other questions:
  • How is the parent function y=x2 related to the given function Y=3(x+1)2?
    7·1 answer
  • The two rectangular prisms are similar.
    6·2 answers
  • PLEASE HELP WITH MATH URGENT!!!! WILL GIVE MANY ALL MY POINTS
    14·1 answer
  • The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard dev
    12·1 answer
  • 15. Fatima bought a video game that has a
    6·1 answer
  • At what point does the curve have maximum curvature? Y = 4ex (x, y) = what happens to the curvature as x → ∞? Κ(x) approaches as
    7·1 answer
  • Someone help 6th grade math i will mark brainliest
    15·1 answer
  • Pls answer :c ! I need help ASAP ! (Math)
    8·1 answer
  • 18 girls to 27 boys simplified
    6·1 answer
  • What type of number is<br> 5<br> 6<br> A) rational<br> B) irrational<br> C) integer<br> D) whole
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!