In an experiment, 15 babies were asked to watch a climber atternpt to ascend a hill On two occasions, the baby withesses the climber fail to make the climb Then, the baby witnesses either a helper toy push the climber up the hill, or a hinderer toy preventing the climber from making the ascent. The toys were shown to each baby in a random fashion. A second part of this experiment showed the climber approach the helper toy. which is not a surprising action, and then the climber approached the hinderar foy, which is a surprising action. The amount of time the baby watched the event was recorded The mean difference in ime spent watching the clinber approach the hinderer tor versus watching the climbar approach the helper toy was 1.25 seconds with a standard deviation of 1.82 seconds. Complete parts a through $C$. 2.66 (Round to two decimal places as needed.) Determine the P value for this hypothesis test. 009 (Round to three decimal places as needed.) State the conchusion for this hypothesis test A. Reject $\mathrm{H}_{0}$. There is not sufficient evidence at the $\alpha=0.01$ level of significance to conclude that the difference is greater than 0 B. Do not reject $H_{0}$. There is not sufficient evidence at the $\alpha=0.01$ level of significance to conclude that the diflerence is greater than 0. C. Reject $H_{0}$. There is sufficient evidence at the $a=0.01$ level of significance to conclude that the diference is greater than 0. D. Do not reject $\mathrm{H}_{0}$. There is sufficient evidence at the $\alpha=0.01$ level of significance to conclude that the dfference is greater than 0.
Solution
Step 1 ：The question is asking to determine the conclusion for a hypothesis test. The hypothesis test is based on the mean difference in time spent watching the climber approach the hinderer toy versus watching the climber approach the helper toy. The mean difference is 1.25 seconds with a standard deviation of 1.82 seconds. The P value for this hypothesis test is 0.009. The significance level is 0.01.
Step 2 ：The null hypothesis H0 is that the difference is not greater than 0. The alternative hypothesis Ha is that the difference is greater than 0.
Step 3 ：If the P value is less than the significance level, we reject the null hypothesis. If the P value is greater than the significance level, we do not reject the null hypothesis.
Step 4 ：In this case, the P value is less than the significance level (0.009 < 0.01), so we reject the null hypothesis.
Step 5 ：Therefore, there is sufficient evidence at the α=0.01 level of significance to conclude that the difference is greater than 0.
Step 6 ：Final Answer: \(\boxed{\text{C. Reject } H_{0}. \text{There is sufficient evidence at the } \alpha=0.01 \text{ level of significance to conclude that the difference is greater than 0.}}\)
