Chapter 9.3, Problem 92E

(a).

To determine

To explain: is it not appropriate to perform a paired t-test in this setting.

Explanation of Solution

Given:

It is given that the designed experiment is about to comparison between the effects of cross-fertilization and self- fertilization on the size of plants.

As per the given data set, there are two variables cross and self.

Interpretation:

Since, a paired t-test is useful for dependent variable (or both experiments has been done on the same land or same items).

Since, both variables are taken as independent variable. Hence, to test the comparison, will use independent t-test.

(b)

To determine

To explain: The conclusion at 0.05 level of significance.

Answer to Problem 92E

There is no enough evidence to conclude that there is any difference between cross and self.

Explanation of Solution

Given:

As per the given table,

The null and alternative hypotheses are:

  $\begin{array}{l}{H}_0:\mu =0\\ H_1:\mu \ne 0\end{array}$

Variable	N	Mean	St Dev	SE Mean	T	P
Diff	15	2.61	4.71	1.22	2.14	0.050

Interpretation:

The null hypothesis is rejected when the p-value is less than level of significance. Here, the p-value (0.050) is not less than level of significance (0.05). Thus, the null hypothesis is not rejected. Therefore, there is no enough evidence to conclude that there is any difference between cross and self.