Heading:____________________ ____/5 Ch.1 Practice Test: The Nature of Probability & Statistics 1. A) B) C) D) An independent variable can also be called a(n) free variable. explanatory variable. suggestive variable. outcome variable. 2. Which branch of statistics would employ probability to predict how many miles one would be able to drive a 2000 Toyota Celica during its lifetime? A) predictive statistics B) descriptive statistics C) inferential statistics D) differential statistics 3. An ad for an exercise product states: "Using this product will burn 74% more calories." This is an example of A) changing the subject B) detached statistics C) suspect samples D) ambiguous averages 4. The variable of height is an example of a quantitative variable. A) True B) False 5. When running an experimental study, the group that is manipulated is called the treatment group. A) True B) False 6. Rating a restaurant by a number of stars is an example of an ordinal level of measurement. A) True B) False Page 1 7. In a true experimental study, the subjects should be assigned to groups randomly. If this is not possible and a researcher uses intact groups, they are performing a A) quasi-experimental study. B) convoluted study. C) cluster study. D) stratified study. 8. Based on Mrs. Smith's electric bill for last year she expects that she will be paying $75/month this year. This is an example of descriptive statistics. A) True B) False 9. Explain the difference between qualitative, quantitative, discrete, and continuous variables. 10. An advertiser states that its brand of energy pills gets into the user's blood stream faster than a competitor's and shows the following two graphs to prove its claim. Why is the comparison misleading? 11. A) B) C) D) Variables with values that are determined by chance are called specialized. erratic variables. random variables. inconsistent variables. Page 2 12. The number of people from the state of Alaska who voted for a Republican in the last election is an example of the ______________ level of measurement. 13. A ______________ consists of all subjects that are being studied. 14. Which of the following correctly describes the relationship between a sample and a population? A) A sample is a group of populations that are subject to observation. B) A population is a group of samples that may or may not be included in a study. C) A sample is a group of subjects selected from a population to be studied. D) A population and a sample are not related. 15. The number of birds in a tree is an example of a continuous variable. A) True B) False 16. If a researcher manipulates one of the variables and tries to determine how the manipulation influences other variables, the researcher is conducting a(n) A) observational study. B) experimental study. C) independent study. D) manipulative study. 17. A) B) C) D) What is the term for a characteristic or attribute that can assume different values? datum variable exponent sample 18. Which branch of statistics would buy a hundred Toyotas, drive them into the ground, record the final mileage, and then write a report for Car and Driver? A) predictive statistics B) descriptive statistics C) inferential statistics D) differential statistics Page 3 19. The four basic methods used to obtain samples are: random, irregular, cluster, and stratified. A) True B) False 20. What level of measurement possesses all the characteristics of interval measurement, and there exists a true zero? A) nominal B) ordinal C) interval D) ratio Page 4 Answer Key 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. B C B A A A A B Qualitative variables can be placed into distinct categories, but they cannot be ranked. Quantitative variables are discrete if they can be assigned a value, generally an integer, and they can be counted. Quantitative variables are continuous if they can assume any value between two specific values. There are no labels or scales on the vertical axes. Hence, the apparent faster speed in the first graph is not necessarily appreciable, as the graph "suggests"; in fact, the speeds might be very close. C ratio population C B B B B B D Page 5