Question

In an​ experiment, 19 babies were asked to watch a climber attempt to ascend a hill. On two​ occasions, the baby witnesses 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 hinderer​ toy, which is a surprising action. The amount of time the baby watched the event was recorded. The mean difference in time spent watching the climber approach the hinderer toy versus watching the climber approach the helper toy was 1.12 seconds with a standard deviation of 1.73 seconds. Complete parts a through c.

(a) State the null and alternative hypotheses to determine if babies tend to look at the hinderer toy longer than the helper toy. Let μd=μ hinderer-μ helper​, where μ hinderer is the population mean time babies spend watching the climber approach the hinderer toy and μ helper is the population mean time babies spend watching the climber approach the helper toy.

A. H0: μd=0 H1:μd≠0

B. H0: μd≠0 H1:μd=0

C. H0: μd<0 H1: μd=0

D. H0:μd=0    H1: μd>0

E. H0:μd>0    H1: μd=0

F. H0:μd=0    H1: μd<0

b. Assuming the differences are normally distributed with no​ outliers, test if the difference in the amount of time the baby will watch the hinderer toy versus the helper toy is greater than 0 at the 0.05 level of significance.

Find the test statistic for this hypothesis test

Determine the​ P-value for this hypothesis test.

State the conclusion for this hypothesis test.

A. Do not reject H0. There is sufficient evidence at the a=0.05 level of significance to conclude that the difference is greater than 0.

B. Do not reject H0. There is not sufficient evidence at the a=0.05 level of significance to conclude that the difference is greater than 0.

C. Reject H0. There is sufficient evidence at the a=0.05 level of significance to conclude that the difference is greater than 0.

D. Reject H0. There is not sufficient evidence at the a=0.05 level of significance to conclude that the difference is greater than 0.

​(c) What do you think the results of this experiment imply about​ babies' ability to assess surprising​ behavior?

A. There is sufficient evidence that babies have the ability to assess surprising behavior.

B. There is not sufficient evidence that babies do not have the ability to assess surprising behavior.

C. There is sufficient evidence that babies do not have the ability to assess surprising behavior.

D. There is not sufficient evidence that babies have the ability to assess surprising behavior.

E. The experiment does not imply anything about​ babies' ability to assess surprising behavior.

Answer 1

n = 19

= 1.12

= 1.73

1) D. H0:μd=0    H1: μd>0

2) Test statistics

t stat = 2.8219

p value = 0.0100

t critical (right tailed test) = 1.7341

As t stat falls in the rejection area, we reject the Null hypotheiss.

Also as the p value is less than , we reject the Null hypotheiss.

C. Reject H0. There is sufficient evidence at the a=0.05 level of significance to conclude that the difference is greater than 0.

A. There is sufficient evidence that babies have the ability to assess surprising behavior.