Question

Three brands of batteries are under study. It is suspected the lives of the three brands are different. An experiment is conducted to test the hypothesis. Five randomly selected batteries of each brand are selected. The time (in hours) until the battery is effectively dead (i.e. power output drops below a specified level) is measured for each battery. What type of analysis is best suited for this study?

Answer 1

The type of analysis that is best suited for this study is ANOVA.

Explanation:

The experiment conducted consists of testing whether the mean lives of the three different brands of batteries are different.

That is a hypothesis test for the difference between more that two means is to be performed.

Analysis of Variance (ANOVA) test is used to perform the hypothesis test for the comparison of more than two means.

The ANOVA test basically compares the variance between the groups with the variance within the group.

The assumptions of an ANOVA test are:

• The populations are normally distributed.
• The samples are independent.
• The variances are equal.
• Samples are of equal sizes.

The hypothesis for ANOVA test is defined as follows:

H₀: There is no difference between the mean, i.e. μ₁ = μ₂ = μ₃

Hₐ: There is a significant difference between the means, i.e. at least one μi ≠ 0.

Thus, the type of analysis that is best suited for this study is ANOVA.