Tag: Hypothesis empirically

What is the name of the hypothesis which states that the observed difference is due to sampling errors created by random sampling?

Independent and Paired Sample t-Tests
Factual Questions

What accounts for the 3-point difference between a mean of 38 and a
mean of 35?

1. Example 1 mentions how many possible explanations for the 3-point difference?

2. What is the name of the hypothesis which states that the observed difference is due to sampling errors created by random sampling?

3. Which of the following statements is true (circle one)?

A. The t test is used to test the difference between two sample means to determine statistical significance.

B. The t test is used to test the difference between two population means to determine statistical significance.

4. If a t test yields a low probability, such as p < .05, what decision is usually made about the null hypothesis?

5. The larger the sample, the (circle one)
A. more likely the null hypothesis will be rejected.
B. less likely the null hypothesis will be rejected.

6. The smaller the observed difference between two means, the (circle one)
A. more likely the null hypothesis will be rejected.
B. less likely the null hypothesis will be rejected.

7. If there is no variation among members of a population, is it possible to have sampling errors when sampling from the population?

8. If participants are first paired before being randomly assigned to experimental and control groups, are the resulting data “independent” or “dependent”?

9. Which type of data tends to have less sampling error (circle one)?
A. Independent
B. Dependent

What does your result in cell A23 mean? Describe it in cell A24. Is the correlation evaluated in cell A15 positive or negative. Put your answer in cell A23.

Exercises

Is the correlation evaluated in cell A15 weak, moderate or strong. Put your answer in cell A22.

Is the correlation evaluated in cell A15 positive or negative. Put your answer in cell A23.

What does your result in cell A23 mean? Describe it in cell A24.

The p value in cell A16 tells you something about a hypothesis. State the null hypothesis in cell A25.

Look at the p value in cell A16. Does it mean that we reject the null hypothesis or that we do not reject it, and why. Put your answer in cell A26.

Compare the t value in cell A17 to the table t value in cell A18.

How does this comparison tell you if you should reject the null hypothesis or not. Put your explanation in cell A27.

Can you conclude that there is a statistically significant Friday effect in the stock market?

Friday Effect”: Are Stock Prices Lower on Fridays?
The prompt:

Many people believe that there is a “Friday effect” in the stock market. They don’t necessarily spell out exactly what they mean by this, but there is a sense that stock prices tend to be lower on Fridays than on other days. Because stock prices are readily available on the Web, it should be fairly easy to test this (alternative) hypothesis empirically. Before collecting data and running a test, however, you must decide exactly which hypotheses you want to test because there are several possibilities.

Formulate at least two sets of null/alternative hypotheses. Then, gather some stock price data and test your hypotheses. Can you conclude that there is a statistically significant Friday effect in the stock market?