Data analysis application problems using inferential statistics

psy_7625-_questions_5-7-unit_1-assignment_1.docx

1. Assume that a population of thousands of people whose responses were used to develop an

anxiety test had scores that were normally distributed with M = 30 and s = 10. What

proportion of people in this population would have anxiety scores within each of the following

ranges of scores?

· Below 20.

· Above 30.

· Between 10 and 50.

2. What is SEM? What does the value of SEM tell you about the typical magnitude of sampling

error?

· As s increases, how does the size of SEM change (assuming that N stays the same)?

· As N increases, how does the size of SEM change (assuming that s stays the same)?

3. Under what circumstances should a t distribution be used rather than the normal distribution