Z-testofOneMean

Contents

1. Title
   
   
2. There are two kinds of questions ...
   
   
3. What is the population's mean?
   
   
4. Did this sample come from that population?
   
   
5. Estimating Confidence Intervals
   
   
6. But how good an estimate is it?
   
   
7. It would be good to know both ...
   
   
8. Here are two clues about how ...
   
   
9. How much sampling variability is there?
   
   
10. Sampling distributions are normal
    
    
11. Three things about sampling distributions
    
    
12. You can be 95% certain that your ...
    
    
13. For example, a random sample of 25 ...
    
    
14. Estimate the SEM like this
    
    
15. What you know about sampling distributions
    
    
16. 95% of all sample means fall within ...
    
    
17. You can be 95% certain that your sample...
    
    
18. In other words, ... in still other words,
    
    
19. The z-test of a single mean
    
    
20. The Evel Kineval Speed Reading School
    
    
21. You take a sample of 36 of their graduates
    
    
22. Is the difference due to sampling variability?
    
    
23. Two competing explanations
    
    
24. The Null Hypothesis
    
    
25. The Alternate Hypothesis
    
    
26. You ALWAYS test the null hypothesis
    
    
27. Is it just a coincidence?
    
    
28. What are the chances of getting ...
    
    
29. The z-test in five easy steps
    
    
30. Step 1. Formulate your hypotheses
    
    
31. Step 2 Choose your confidence level
    
    
32. Step 3. Determine the critical value of z
    
    
33. What you do with the critical value
    
    
34. Step 4. Calculate your observed value of z
    
    
35. Example calculation of z
    
    
36. Step 5. Compare observed z to critical z
    
    
37. A picture showing the comparison
    
    
38. Interpreting the result of the test
    
    
39. Blank Slide
    
    

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Z-test of one mean

Last updated:
August 6, 2005

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