In: Statistics and Probability
Classic Golf Inc. manages five courses in the Jacksonville, Florida, area. The director of golf wishes to study the number of rounds of golf played per weekday at the five courses. He gathered the following sample information.
Day | Rounds | ||
Monday | 100 | ||
Tuesday | 125 | ||
Wednesday | 110 | ||
Thursday | 145 | ||
Friday | 145 | ||
At the 0.05 significance level, is there a difference in the number of rounds played by day of the week?
H0: Rounds played is the same for each
day.
H1: Rounds played is not the same.
State the decision rule, using the 0.05 significance level. (Round your answer to 3 decimal places.)
Classic Golf Inc. manages five courses in the Jacksonville, Florida, area. The director of golf wishes to study the number of rounds of golf played per weekday at the five courses. He gathered the following sample information.
Day | Rounds | ||
Monday | 100 | ||
Tuesday | 125 | ||
Wednesday | 110 | ||
Thursday | 145 | ||
Friday | 145 | ||
At the 0.05 significance level, is there a difference in the number of rounds played by day of the week?
H0: Rounds played is the same for each
day.
H1: Rounds played is not the same.
State the decision rule, using the 0.05 significance level. (Round your answer to 3 decimal places.)
Reject H0 if chi-square >
Compute the value of chi-square. (Round your answer to 3 decimal places.)
Chi-square value
Compute the value of chi-square. (Round your answer to 3 decimal places.)
Solution:
Here, we have to use chi square test for goodness of fit.
Null hypothesis: H0: Rounds played is the same for each day.
Alternative hypothesis: Ha: Rounds played is not the same.
We assume level of significance = α = 0.05
Test statistic formula is given as below:
Chi square = ∑[(O – E)^2/E]
Where, O is observed frequencies and E is expected frequencies.
We are given
N = 5 days
Degrees of freedom = df = N – 1 = 5 – 1 = 4
α = 0.05
Critical value = 9.487729037
(by using Chi square table or excel)
Decision rule: Reject H0 if test statistic Chi square > 9.488
Calculation tables for test statistic are given as below:
Day |
O |
E |
(O - E)^2/E |
Monday |
100 |
125 |
5 |
Tuesday |
125 |
125 |
0 |
Wednesday |
110 |
125 |
1.8 |
Thursday |
145 |
125 |
3.2 |
Friday |
145 |
125 |
3.2 |
Total |
625 |
625 |
13.2 |
Test Statistic = Chi square = ∑[(O – E)^2/E] = 13.2
χ2 statistic = 13.200
P-value = 0.010338797
(By using Chi square table or excel)
P-value < α = 0.05
So, we reject the null hypothesis
There is sufficient evidence to conclude that there is a difference in the number of rounds played by day of the week.