Question

Two batches of tablets were prepared by two different processes. The potency determinations made on five tablets from each batch were as follows:

• batch A: 5.8, 4.2, 4.6, 5.5, 5.6;
• batch B: 4.5, 4.8, 5.5, 5.2, 4.4.

Test to see if the means of the two batches are equal. Explain how you do that. State your null and alternative hypothesis.

Answer 1

Bring data in to excel sheet.

Go to data tab --> choose data analysis --> choose t-Test: Paired Two Sample for Means statistics

Click ok and populate the results

So the means of the two batches are not equal

Batch A means: 5.14

Batch B means: 4.88

The standard form tests the following hypotheses:

Null: The two-population means are equal.

Alternative: The two-population means are not equal

In Hypothesized Mean Difference, you’ll typically enter zero. This value is the null hypothesis value, which represents no effect. In this case, a mean difference of zero represents no difference between the two methods, which is no effect.

a default Alpha value of 0.05, which is usually a good value. Alpha is the significance level

P-value = 0.59 which is greater than the alpha 0.05

A p-value higher than 0.05 (> 0.05) is not statistically significant and indicates strong evidence for the null hypothesis. This means we retain the null hypothesis and reject the alternative hypothesis. You should note that you cannot accept the null hypothesis, we can only reject the null or fail to reject it