Using a slightly modified example problem from a prior exercise:

__Example:__A scientist creates a chemical which he believes changes the temperature of water. He applies this chemical to water and takes the following measurements:

__Summary Data Pertaining to First Set of Measurements__

N = 8

SD = 2.167124

Mean = 72.875

He then measures temperature in samples which the chemical was not applied.

__Summary Data Pertaining to the Second Set of Measurements__

N = 8

SD = 1.669046

Mean = 75.25

Can the scientist conclude, with a 95% confidence interval, that his chemical is in some way altering the temperature of the water?

To perform this analysis, select

**“Compare Means”**from the

**“Analyze”**drop down, then select

**“Summary Independent-Samples T Test”**.

You should be presented with the menu below. Simply enter the information that was provided in the example problem and click

**“OK”**. You have the option to change the Confidence Level (%), but since we are assuming a 95% confidence level, doing so is un-necessary.

This presents the output:

From this output we can conclude:

With a p-value of 0.028 (.028 < .05), and a corresponding t-value of - 2.456, we can state that, at a 95% confidence interval, that the scientist's chemical is altering the temperature of the water.

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