This is page twenty-one of the series of free video lessons, "Statistics Lectures".
Statistics - Lecture 62
Independent Samples t-Test
A statistics teacher wants to compare his two classes to see if they performs any differently on the tests he gave that semester. Class A has 25 students with an average score of 70, standard deviation 15. Class B has 20 students with an average score of 74, standard deviation 25. Using alpha 0.05, did these two classes perform differently on the tests?
1. Define Null and Alternative Hypothesis
2. State Alpha
3. Calculate Degrees of Freedom
4. State Decision Rule
5. Calculate Test Statistic
6. State Results
7. State Conclusion
Statistics - Lecture 63
Confidence Intervals for Independent Samples t-Test
We use the Independent Samples t-Test to test if two sample means are different from one another.
After the t-Test, confidence intervals can then be constructed to estimate how large that mean difference is.
Statistics - Lecture 64
Effect Size for Independent Samples t-Test
The effect size allows us to measure the magnitude of mean differences.
Statistics - Lecture 65
Dependent Samples t-Test
Researches want to test a new anti-hunger weight loss pill. They have 10 people rate their hunger before and after taking the pill. Does the pill do anything? Use alpha = 0.05.
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