Let's perform a dependent samples t-test: Researchers want to test a new anti-hunger weight loss pill. They have 10 people rate their hunger both before and after taking the pill. Does the pill do anything? Use alpha = 0.05

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Steps for Dependent Samples t-Test |
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1. Define Null and Alternative Hypotheses 2. State Alpha 3. Calculate Degrees of Freedom 4. State Decision Rule 5. Calculate Test Statistic 6. State Results 7. State Conclusion |

Let's begin.

1. Define Null and Alternative Hypotheses

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2. State Alpha

Alpha = 0.05

3. Calculate Degrees of Freedom

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4. State Decision Rule

Using an alpha of 0.05 with a two-tailed test with 9 degrees of freedom, we would expect our distribution to look something like this:

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Use the t-table to look up a two-tailed test with 9 degrees of freedom and an alpha of 0.05. We find a critical value of 2.2622. Thus, our decision rule for this two-tailed test is:

If t is less than -2.2622, or greater than 2.2622, reject the null hypothesis.

5. Calculate Test Statistic

The first step is for us to calculate the difference score for each pairing:

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Now, we can calculate our t value:

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6. State Results

t = 3.61

Result: Reject the null hypothesis.

7. State Conclusion

The anti-hunger weight loss pill significantly affected hunger, t = 3.61, p < 0.05.