Answer the following questions, covering material from Ch. 13 of Methods in Behavioral Research:

1. Define inferential statistics and how researchers use inferential statistics to draw conclusions from sample data. (3 points)

According to Cozby (2009),”inferential statistics are used to determine whether we can, in fact, make statements that the results reflect what would happen if we were to conduct the experiment again and again with multiple samples” (pg. 245).

2. Define probability and discuss how it relates to the concept of statistical significance. (2 points)

Probability is the possibility that an outcome of an experience or an event will occur (Cozby, 2009). Probability and significance are one in the same. For instance if the statistical significance is low then the difference will be counted as a random error, whereas if it is high it will not. If the significance is low then the probability is considered sound.

3. Explain the relationship between the alpha level (or significance level) and Type I error. What is a Type II error? How are Type I and Type II errors different? (3 points)

A significance level α corresponds to a certain value of the test statistic,
So the probability of rejecting the null hypothesis when it is true is the probability that t > tα, which is α.
In other words, the probability of Type I error is α.1 A Type I error occurs when your reject a true null hypothesis (remember that when the null hypothesis is true you hope to retain it). A Type II error occurs when you fail to reject a false null hypothesis (remember that when the null hypothesis is false you hope to reject it). The best way to allow yourself to set a low alpha level (i.e., to have a small chance of making a Type I error) and to have a good chance of rejecting the null when it is false (i.e., to have a small chance of making a Type