Math Problem Statement
Please solve
Solution
Let's solve the problem step by step.
Part (a) What is the level of significance?
The level of significance is (5%).
Null and Alternative Hypotheses:
- (The variance is equal to 47.1.)
- (The variance is greater than 47.1.)
This is a one-tailed chi-square test for variance.
Part (b) Chi-Square Test Statistic
The formula for the chi-square test statistic is:
Where:
- (sample size),
- (sample variance),
- (population variance).
Substitute the values:
Degrees of Freedom (df):
Assumption: We assume the population follows a normal distribution.
Part (c) P-Value of the Sample Test Statistic
Using the chi-square table or software, we determine the p-value for with in a one-tailed test.
- From tables or software: .
Part (d) Decision: Reject or Fail to Reject ?
- The decision rule is: Reject if .
- Since , we reject the null hypothesis.
Part (e) Interpretation
At the 5% level of significance, there is sufficient evidence to conclude that the variance of annual salaries is greater in Kansas.
Final Answers:
(a) Level of Significance: .
, .
(b) Chi-Square Test Statistic: , .
Assumption: Normal population distribution.
(c) P-Value: .
(d) Decision: Reject .
(e) Interpretation: There is sufficient evidence to conclude the variance is greater in Kansas.
Would you like a detailed breakdown of any step? Here are 5 questions to expand:
- How is the chi-square formula derived for variance testing?
- Can you explain how to use the chi-square distribution table?
- Why is it necessary to assume a normal population distribution?
- What happens if is changed to a more strict value, e.g., 1%?
- What are other statistical tests for variance aside from chi-square?
Tip: Always double-check your and p-values with tables/software for precision!
Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Chi-Square Test
Hypothesis Testing
Variance
Statistical Inference
Formulas
\chi^2 = \frac{(n-1) \cdot s^2}{\sigma^2}
df = n - 1
Theorems
Chi-Square Distribution
Hypothesis Testing for Variance
Suitable Grade Level
College/University
Related Recommendation
Chi-Square Test for Variance: Hypothesis Testing Example with Step-by-Step Solution
Hypothesis Testing for Variance Using Chi-Square Distribution
Chi-square Test for Variance: Hypothesis Testing with Sample Standard Deviation
Chi-Square Test for Variance: Sample Variance of 80 vs Population Variance of 100
Writing the Null Hypothesis and Making Decisions Using the Pearson Chi-Square Test