Self-Assessment Module 9




Introduction Instructions Resources Assessment 1. Algebraic Notation and Operations 2. Descriptive Statistics 3. Tabular Displays of Data 4. Graphical Displays of Data 5. Research Topics, Theory, Constructs, Questions, and Hypothesis 6. Research Designs 7. Measurement 8. Sampling 9. Probability 10. Basics of Inferential Statistics 11. One-Group Inferential Statistics 12. Two-Group Inferential Statistics 13. Critiquing Education and Social Science Research Answer Key		Module 9: Probability This section assesses understanding of probability, which is important in the interpretation of inferential statistics. Question 1: If a school district has 6,000 African American students, 3,000 Latino students, and 1,000 Asian students, what is the probability of drawing a Latino student in one random draw? A. 1/300 B. .3 C. 300/700 D. 1/700 E. None of the above Question 2: Which is more likely to occur: something with a probability of .05, something with a probability of .1, or something with a probability of .018? A. .1 B. .05 C. .018 D. Both (A) and (C) E. None of the above Question 3: If something has a .05 probability of happening, what is the probability of it not happening? A. Sufficient information has not been provided B. .05 C. 99.5 D. .95 E. None of the above Question 4: What is the maximum possible probability with which something can happen? A. 0.5 B. 1.00 C. Infinity D. All the time E. None of the above Question 5: If the probability of X occurring is .2 and the probability of Y occurring is .4, and X and Y are independent of each other, what is the probability of X and Y both occurring? A. .6 B. .5 C. .20 D. .08 E. None of the above Question 6: If the probability of X occurring is .2 and the probability of Y occurring is .4, and X and Y are independent of each other, what is the probability of either X or Y occurring? A. .4 B. .6 C. .80 D. .96 E. None of the above Question 7: If, each month from September through May, we draw a random sample of 10 students from the school district in (Question 9-1) to monitor student opinion, about how constant or varying is the ratio of the three racial groups likely to be across the nine samples? A. The ratio is likely to be 6:3:1 in every sample B. The ratio is likely to be approximately 6:3:1 in every sample C. The ratio is likely to vary substantially from 6:3:1 in some of the samples D. Insufficient information for answering E. None of the above Question 8: Now, if, each month, we draw a random sample of 1,000 students from the school district in (10-1) to assess student opinion, about how constant or varying will be the ratio of the three racial groups across the nine samples? A. The ratio is likely to be 6:3:1 in every sample B. The ratio is likely to be approximately 6:3:1 in every sample C. The ratio is likely to vary substantially from 6:3:1 in some of the samples D. Insufficient information for answering E. None of the above Question 9: Let's say we draw a random sample of 20 from a company of 3,000 employees and find that 3 hate their jobs, 10 are satisfied with their jobs, and 7 love their jobs. What would be the prudent inference to make about the ratio of job satisfaction in the company? A. The ratio is 3:10:7 B. The ratio is about 3:10:7 C. The ratio is roughly 3:10:7 D. The ratio cannot be prudently inferred from this information E. None of the above Question 10: Let's say we draw a random sample of 1,000 from a company of 3,000 employees and find that 150 hate their jobs, 500 are satisfied with their jobs, and 350 love their jobs. What would be the prudent inference to make about the ratio of people of job satisfaction in the company? A. The ratio is 3:10:7 B. The ratio is about 3:10:7 C. The ratio is roughly 3:10:7 D. The ratio cannot be prudently inferred from this information E. None of the above