1. Hypothesis Testing with z using the p-Value method and TI-84 This is a copy of the other presentation, which uses the Classical, or Critical Value Method

2. Example 1

3. Example 1, continued

4. Example 1 initial direction

5. Step 1. State the hypotheses

6. Step 2: Compute the Test Value Step 3: Compute its p-Value TI-84 Inputs STAT, TESTS, 1:Ztest

7. Step 2: Compute the Test Value Step 3: Compute its p-Value TI-84 Outputs From the “Calculate” It reminds us of the Alternative Hypothesis. z = the test value, not needed, but interesting p = the p value of that test value. It repeats the sample mean and sample size.

8. Step 4. Make a Decision Rules for a One-Tailed TestIn this particular problem

9. A remark about our decision

10. Step 5. Plain English conclusion The conclusion has to be suitable for a general audience. They don’t want to hear any Statistics lingo. Say something that a journalism school major could read in a news report. Here’s what we can say: “There is NOT enough evidence to conclude that these rivets are SIGNIFICANTLY weaker than the required strength.”

11. Example 2

12. Example 2 remarks We scored higher, that’s for sure. 83.15 vs. 79.68 statewide. But we have to be careful before issuing a press release or using these results as a recruiting tool We want the Central Limit Theorem to tell us that these results are too good to be mere coincidence.

13. Example 2 initial direction

14. Step 1. State the hypotheses

15. Step 2. Compute the Test Value. Step 3. Compute its p Value

16. Step 4. Make a Decision Rules for a One-Tailed TestIn this particular problem

17. Remarks about our decision If our students had scored 80 or 81 or so, it would have been higher, but not significantly higher. The Central Limit Theorem would have explained it as just variations in sampling. But we have something really big here, something improbable according to the C.L.T. Less than 1% chance this result was just luck.

18. Step 5. Plain English conclusion The conclusion has to be suitable for a general audience. They don’t want to hear any Statistics lingo. Say something that a journalism school major could read in a news report. Here’s what we can say: “Darton State College EMT students scored significantly higher than the statewide average in a recent examination.”

19. Example 3

20. Example 3 initial direction

21. Step 1. State the hypotheses

22. Step 2. Determine the Test Value. Step 3. Determine its p value.

23. Step 4. Make a Decision Rules for a Two-Tailed TestIn this particular problem

24. Remarks about our decision The racing fans at our track were certainly younger than the supposed average age of 55. But it wasn’t strong enough evidence. So we let the null hypothesis stand. We did NOT “prove” the null hypothesis. We merely collected evidence that mildly disagreed with the null hypothesis.

25. Step 5. Plain English conclusion The conclusion has to be suitable for a general audience. They don’t want to hear any Statistics lingo. Say something that a journalism school major could read in a news report. Here’s what we can say: “We can’t disagree that the average age of a horse racing fan really is 55 years old, despite a little bit of evidence to the contrary.”