In: Statistics and Probability
The amount of oxygen consumption was measured in seven individuals over two periods of time while sitting with their eyes closed. During the first period, they listened to an exciting adventure story; during the second period of time, they heard restful music. The researcher is not sure whether participants will consume more or less oxygen during the story compared with the music. Here are their results:
Subject |
Story |
Music |
1 |
5.8 |
5.3 |
2 |
8.1 |
7.2 |
3 |
6.4 |
6.3 |
4 |
7.8 |
6.1 |
5 |
4.6 |
5.1 |
6 |
5.1 |
4.8 |
7 |
6.6 |
6.1 |
B)
SOLUTION A: STEP 1 NULL HYPOTHESIS H0:
ALTERNATIVE HYPOTHESIS Ha:
(2) Rejection Region
Based on the information provided, the significance level is α=0.05, and the degrees of freedom are df=6.
Hence, it is found that the critical value for this two-tailed test is tc=2.447, for α=0.05 and df=6.
The rejection region for this two-tailed test is R={t:∣t∣>2.447}.
(3) Test Statistics
The t-statistic is computed as shown in the following formula:
(4) Decision about the null hypothesis: Since it is observed that ∣t∣=1.936≤tc=2.447, it is then concluded that the null hypothesis is not rejected.
Using the P-value approach: The p-value is p=0.1009, and since p=0.1009≥0.05, it is concluded that the null hypothesis is not rejected.
(5) Conclusion: It is concluded that the null hypothesis Ho is not rejected. Therefore, there is not enough evidence to claim that the population mean μ1 is different than μ2, at the 0.05 significance level.
c) We don't have sufficient evidence to conclude that participants will consume more or less oxygen during the story compared with the music.