Biostatistics Final Exam Multiple Choice PDF

Biostatistics Final Exam Multiple Choice Exam #1 1. A ____ is a complete collection of all measurements or data, whereas a ____ is a sub collection of scores selected from the complete collection a. Sample; population b. Population; sample c. Sample; census...

Biostatistics Final Exam Multiple Choice Exam #1 1. A ____ is a complete collection of all measurements or data, whereas a ____ is a sub collection of scores selected from the complete collection a. Sample; population b. Population; sample c. Sample; census d. Population; parameter 1b. A ______ is a numerical measurement describing some characteristic of a population. A ________ is a numerical measurement describing some characteristic of a sample. a. Parameter; statistic b. Statistic; parameter c. Census; demographic d. Framework; statistic 2. A wildlife biologist measures the surface temperature (in degrees Celsius) of the water in the James River. Which scale of measurement applies to these scores? a. Nominal b. Ordinal c. Interval d. Ratio 2b. A group of cross-country runners all finish a race and the completion time is recorded for each individual. Which scale of measurement applies to these scores? a. Nominal b. Ordinal c. Interval d. Ratio 3. A graduate student in public health conducts a study on smoking habits in undergraduate students. She begins with a survey of 500 randomly selected undergraduate students from 10 randomly selected universities in the U.S. Which of the following is the population of interest for her study? a. 500 undergraduate students from 10 U.S. universities b. Undergraduate students from U.S. universities c. University students d. Smokers in the U.S. 4. A group of wildlife biologists plan to trap, radio collar and track 100 female foxes in each of the 5 regions: Neartic, Paleartic, Orietnal, Ethiopian, and Australia (total n = 500). In the spring, the researchers will examine the den of each subject to determine the number of offspring produced during the breeding season. Which of the following sampling techniques is being used? a. Systematic b. Convenience c. Stratified d. Cluster 4b. A group of wildlife biologists plan to trap, radio collar and track 100 female foxes in each of the 5 regions: Neartic, Paleartic, Orietnal, Ethiopian, and Australia (total n = 500). In the spring, the researchers will choose 3 of the 5 regions to determine the number of offspring produced during the breeding season of all members in each region. Which of the following sampling techniques is being used? e. Systematic f. Convenience g. Stratified h. Cluster 5. A sample of 80 juvenile salmon is grouped into the following frequency distribution according to their weights: Weight (in grams) Frequency 100-149 15 150-199 10 200-249 30 250-299 25 If you produced a histogram based upon the data above, the distribution of weights in the juvenile salmon would appear to be ____. a. Normal b. Skewed right (positively) c. Uniform d. Skewed left (negatively) 5b. A sample of 80 juvenile salmon is grouped into the following frequency distribution according to their weights: Weight (in grams) Frequency 100-149 25 150-199 30 200-249 10 250-299 15 If you produced a histogram based upon the data above, the distribution of weights in the juvenile salmon would appear to be ____. e. Normal f. Skewed right (positively) g. Uniform h. Skewed left (negatively) 6. A nurse measured the blood pressure of each person who visited her clinic. To the right is a histogram for the systolic blood pressure readings for patients aged between 25 and 40 years (given to the nearest whole number). Approximately what percentage of the sample had a systolic blood pressure reading between 110 and 119 mmHg (inclusive)? a. 35% b. 2.5% c. 30% d. 0.35% 6b. A nurse measured the blood pressure of each person who visited her clinic. To the right is a histogram for the systolic blood pressure readings for patients aged between 25 and 40 years (given to the nearest whole number). Approximately what percentage of the sample had a systolic blood pressure reading between 120 and 125 mmHg (inclusive)? a. 20% b. 0.20% c. 15% d. 0.15% 7. The scatter plot below displays the amount of nitrous oxide (NO) and the amount of carbon monoxide (CO) emissions in metric tons over a 10 year period in the U.S. Which choice best describes any relationship between these two measures? a. There is a negative linear association between NO and CO b. There is a positive linear association between NO and CO c. There is little association between NO and CO d. Rising CO levels cause NO levels to rise as well 8. The two key parts of the regression equation involve the ____ and the ____. a. Slope; y-intercept b. Asymptote; slope c. Slope; x-intercept d. Y-intercept; asymptote 9. The ____ coefficient, r, measures the ____ of the linear association between two variables. a. Probability, direction b. Exponential, determinative c. Reliability, Discriminant function d. Correlation, strength 10. A hospital administrator wishes to monitor the distribution of crash cart supplies to make sure that there are not unacceptable losses over time. Which of the following graphs would be most useful to produce for him? a. Pareta chart b. Time-series chart c. Pie chart d. Histogram 11. A ____ is a score that is so extreme as to bring into question whether the score should be included in the distribution of scores in the sample. a. Z-score b. Range dispersal c. Outlier d. Slump 12. While the ____ is sensitive to the value of an outlier, the ____ is not. a. Standard deviation; variance b. Mode; mean c. Median; mode d. Mean; median 13. A ____ score expresses the value of that score relative to the mean and standard deviation of the sample distribution. a. Standard b. Raw c. Decentralized d. Hypergeometric 14. The standard normal distribution ____. a. Is symmetrical and unimodal b. Has a mean, median and mode all equal to zero (0) c. Has an area equal to 1.0 d. Has all of the above characteristics 15. A large study of serum cholesterol levels in patients with diabetes mellitus reveals that the parameter is normally distributed with a mean of 230 mg/dL and standard deviation of 10 mg/dL. According to these results 95% of serum cholesterol in these patients lie between which of the following limits? a. 220 and 240 mg/dL b. 225 and 235 mg/dL c. 210 and 250 mg/dL d. 200 and 260 mg/dL 16. A ____ is constructed in such a manner as that each member of the population has an equal chance of being selected. a. Systematic sample b. Random sample c. Stratified sample d. Determinate sample 17. Experimenters manipulate ____ variables in order to detect changes in ____ variables. a. Independent; dependent b. Dependent; independent c. Random; systematic d. Control; extraneous  18. The extent to which scores in a sample (or population) differ from one another is known as ____ a. Homogeneity b. Kurtosis c. Skewness d. Dispersion 19. Distribution that as “flatter” than normal distribution are _____ a. Platykurtic b. Mesokurtic c. Leptokurtic d. Kleptokurtic 20. The ____ tells you when a distribution is asymmetrical. a. Kurtosis b. Skewness c. Halitosis d. Z-test Exam #2 1. Events that are ____ are not likely to be due to chance or random error. a. Coincidental b. Statistically significant c. Spurious d. Specious 2. Which of the following statements is FALSE? a. If the probability of an event is 0, then it is impossible for that event to occur. b. If P(A) = 0, then the probability of the complement of A is 1. c. If the probability of an event is 1.5, then it is certain for that event to occur. d. A probability value can never be < 0. 3. Which of the three is NOT a common approach to knowing the probability of an event? a. Relative Frequency Approximation b. Classical Approach c. Subjective Approach d. These are all common approaches to finding the probability of an event 4. We would denote the conditional probability of event B occurring, given that event A has already occurred as ____. a. P (B│A) b. P (A│B) c. P(B) P(A) d. P(A - B) / P(A) 5. Under conditions for Bayes theorem, a ____ is the initial probability value obtained before an additional information is provided while a ____ is a review probability value which has been updated using information obtained afterward. a. Posterior probability; prior probability b. Prior probability; posterior probability c. Priori; certiorari d. Certiorari; priori 6. Select the procedure that does NOT result in a binomial distribution. a. Surveying dental partners and asking if they experienced anxiety at any point during their appointment b. Surveying dental patients and asking them if they did or did not floss before their appointment c. Surveying dental patients and asking them if they have dental insurance d. Surveying dental patients and asking them their relative level of satisfaction after their appointment 7. A field biologist was interested in foraging success by ring-billed gulls at a local beach. She sat in an inconspicuous location in a corner of the beach, and randomly selected 75 gulls upon each arrival in the observation zone. She notes the arrival time and departure time of each subject, and she tracked the feeding responses for each subject during the foraging bout. The researcher recorded the total time foraging and number of food items captured by each subject. Identify the types of variables recorded by the researcher. a. Number of items - discrete; total time - continuous b. Number of items - continuous; total time - continuous c. Number of items - continuous; total time - discrete d. Number of items - discrete; total time - discrete 8. A random variable is ____. a. Generated by the logarithmic transformation of a systematic variable b. The quantity for which an algebraic equation is solved c. A qualitative attribute of a population d. A variable with a single numerical value, determined by chance, for each outcome of a procedure 9. The SUM of the probabilities of a discrete probability distribution must be ____. a. Between zero and one b. Greater than one c. Equal to one d. Less than or equal to zero 10. Which of the below is not a requirement for binomial experiment? a. The experiment is performed a fixed number of times b. The trials are interdependent; the outcome of one trial is determined by the outcome of a previous trial c. For every trial, there are exactly two mutually exclusive outcomes d. The probability of success if fixed across all trials 11. Given that a Poisson probability distribution applies to occurrences of some event over a specific interval, the probability of success for any of these intervals _____. a. Is the same b. Is complementary c. Is the reciprocal of the √n d. Is none of these 12. Which of the following is a biased estimator? → median, range, standard deviation a. Sample proportion b. Sample mean c. Sample standard deviation d. Sample variance 13. Which of the following is an unbiased estimator? → mean, variance, proportion a. Sample range b. Sample variance c. Sample interquartile range d. Sample median 14. The bigger the sample size (n), the more likely the sample statistics are representative of the population parameters. This is also known as the ____. a. Area under the curve b. Overestimation rule c. Law of large numbers d. Alpha level  15. According to the Central Limit Theorem, the distribution of scores in a population should be ____ if the scores within samples of n > 30 are too likely to be normally distributed. a. Normally distributed b. Uniformly distributed c. Systematically distributed d. Of any distribution possible Exam #3 1. As the ____ increases, the t-distribution approximates the shape of the standard normal distribution (i.e. the z-distribution). a. Sample size b. Variance c. Mean difference d. Kurtosis 2. You are constructing a confidence interval estimate of µ. When the σ is ____ and the sample size is greater than 30, you would use the ____ distribution. a. Known; Student’s t b. Unknown; normal (z) c. Unknown; Student’s t d. None of the above 3. Which of the following distributions would you use in constructing the confidence interval estimate of σ2? a. Student’s t b. Normal z c. F d. X2 3b. The ______ is the probability of calculating a particular value of the test statistic if the null hypothesis is true. a. Confidence interval b. Critical value c. Alpha value d. P-value 4. The margin of error ____ with an increase in sample size. a. Increases b. Decreases c. Remains constant d. Varies independently 5. Which of the following do you need to know if you wish to determine the sample size required to appropriately estimate µ? a. The desired margin of error, E b. The alpha level, a c. The population standard deviation, σ (can be either known or estimated with x) d. All of the above 6. The decision to reject a true null hypothesis is known as a ____, and the probability of doing so is ____. a. Type I error; Alpha b. Type I error; Beta c. Type II error; Alpha d. Type II error; Beta 7. The decision to fail to reject a false null hypothesis is known as a ____ and the probability of doing so is ____. a. Type I error; Alpha b. Type I error; Beta c. Type II error; Alpha d. Type II error; Beta 8. The ability of a procedure to detect differences that are real (e.g. reject a false null hypothesis) is known as the ____ of the statistical procedure, and the probability of rejecting a false null hypothesis is ____. a. Power; 1 - α b. Power; 1 - β c. Specificity; α - β d. Specificity; β - α 9. A statistical procedure is said to be ____ if it maintains the probability of a Type I error, even if an assumption or requirement of the procedure is violated. a. Biased b. Unbiased c. Robust → statistics that yield good performance when data is drawn from a wide range of probability distributions d. Powerful 10. The between-subjects design is to the ____ as the within subject design is to the ____. a. Dependent Samples t-test; Matched Pairs t-test b. Independent Samples t-test; Dependents Samples t-test c. Matched Pairs t-test; Independent Samples t-test d. Matched Pairs t-test; Dependent Samples t-test  11. What is the advantage to pooling the variance in an Independent Samples t-test? a. The confidence intervals are wider, decreasing the value of 1 - α b. The hypothesis test has less power, decreasing the chance of a Type II error c. The degrees of freedom are increased, reducing the critical value of t d. The likelihood of a Type I error is smaller, decreasing the critical value of 1 - β 12. Which of the following are requirements/assumptions of the Related Samples t- test? a. The sample data are independent b. The sample data are dependent c. Both samples are systematically sampled from the population d. All of the above 13. Which of the following are characteristics of the F distribution? a. All possible values of F are positive b. The distribution of F is asymmetric, with a positive (right) skew c. If both sample variance are equal, then F = 1.0 d. All of the above 14. Which of the following statistics would you use if you were comparing proportions from two samples? a. Normal (z) b. Student’s t c. F d. X2 14b. Which of the following statistics would you use if you were comparing the means from two independent samples when σ12 and σ22 are both unknown? a. Student’s t b. Normal (z) c. F d. X2 15. A psychotherapist claims that the mean amount of time that women (group 1) spend on talk therapy is more than that of men (group 2). What is the alternative hypothesis for his statistical test? a. H1: µ1 > µ2 b. H1: µ2 = µ2 c. H1: µ1 < µ2 d. H1: µ1 not equal µ2 Exam #4 1. Which of the following is NOT a possible value for a correlation coefficient (r)? a. 0.0 b. -0.3 c. 0.3 d. 10.1 2. When the changes in one variable are related to systematic changes in another variable, the two variables are said to ____. a. Covary b. Comingle c. Regress to the mean d. Account for variance 3. The technique of ____ is used to predict one set of scores from a second set of obtained scores a. Analysis of variance b. Hypergeometric transformation c. Score standardization d. Linear regression 4. Because of the ____, it is inappropriate to infer causation from correlational findings. a. Directionality problem b. “Lurking Variable” (or 3rd variable) problem c. Both A and B d. Neither A nor B 5. The difference between the predicted score Ŷ, and the actual score Y, is also known as the ____ which is used in calculating the standard error of the estimate. a. Residual b. Covariance c. Eigenvalue d. Coefficient of Determination 6. A(n) ____ is a point lying far away from the other data points on a scatter plot. a. Outlier b. Margin of error c. Residual point d. Normative score 7. The F-statistic is a ratio of the ____ and ____ a. Within Groups Variance; Between Groups Variance b. Between Groups Variance; Within Groups Variance c. Total Variance; Systematic Variance d. Total Variance; Unsystematic Variance 8. Which of the following is NOT a mathematically possible value of the F-statistic? a. 0.0 b. 1.0 c. -1.0 d. 10.0 9. Which of the following are requirements/assumptions of the two-factor between subjects ANOVA? a. The scores are systematically selected from the population of interest b. The variance of the scores in the populations are unequal c. The sample values come from a population with a normal distribution d. The null hypothesis is false 10. Which of the following are required to justify the application of a post hoc statistical test such as the Bonferroni test? a. A significant ANOVA f-test b. More than two levels of the factor/independent variable c. Unplanned comparisons between groups d. All of the above 11. Which of the following contribute to variations in a set of scores/measurements? a. Individual differences among subjects b. Uncontrolled extraneous variables c. The effects of the Independent Variable d. All of the above 12. If participants are experiencing ALL levels of a treatment, a ____ is being used. a. Mixed Factorial Design b. One factor within subjects design (AKA Repeated-Measures) c. One factor between subjects design d. Two factor between subjects design 13. Regarding the subjects exposure to treatment conditions under the Independent Variable, the between-subjects design is to ____ as the within subjects design is to ____. a. Or; And b. Peanut Butter; Jelly c. A Tourniquet; A Band-Aid d. Heteroscedasticity; Homogeneity of Variance 14. The problem of ____ indicates that an important requirement/assumption of the One Way between subjects ANOVA has been violated and that ____ becomes an important consideration for the ANOVA to be robust. a. Sphericity; Type II Error b. Heterogeneity of variance; equal sample sizes c. Heteroscedasticity; power/resolution d. Type I Error; sample independence 15. What makes the Repeated-Measures ANOVA more powerful than the comparable One Way Between Subjects ANOVA? a. The reduction in the df of the denominator of F b. The increase in the df of the numerator of F c. The removal of SSsubjects from the error term d. The reduced likelihood of a Type I error