BST 322 Week 2 Test Questions with Correct Answers

BST 322 Week 2 Test Questions with Correct Answers Sampling error - Answer-Error in a statistical analysis arising from the unrepresentativeness of the sample taken.Reflects the tendency for statistics to fluctuate from one sample to another. Sampling distribution - Answer-Are actually probability distributions, is central to estimates of sampling error. Sampling distribution of the mean - Answer-A theoretical probability distribution of the means of an infinite number of samples given size from a population. Standard error of the mean - Answer-The standard deviation of the sampling distribution of the sample mean. Point estimation - Answer-Involves calculating a single statistics to estimate the parameter. Confidence interval - Answer-Result adjusted by adding and subtracting the margin of error Null hypothesis - Answer-The hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error. Alternate hypothesis - Answer- Type I error - Answer-false positive Type II error - Answer-false negative Alpha level - Answer-Indicates the area in the theoretical probability distribution that corresponds to the rejection of the null hypothesis. Beta - Answer-The probability of making a Type II error. Power - Answer-The probability that a test will reject a false null hypothesis. Parametric tests - Answer-Involve estimating a parameter Non-parametric tests - Answer-Do not test hypotheses about population parameters. One-tailed test - Answer-Is one in which the critical region is in only one end of the distribution. Two-tailed test - Answer-Is one that uses both tails of a sampling distribution to determine the critical region for rejecting the null hypothesis. Critical region - Answer-Acceptance region on the theoretical distribution, and to accept the null hypothesis otherwise. Degrees of freedom - Answer-Is a concept used in statistical testing to indicate the number of components that are free to vary about a parameter. One-sample t-test - Answer- Standard error of the difference - Answer-SEd summarizes how much sampling error occurs, on average, when a mean difference score is computed, for samples of a given size. Independent groups t-test - Answer-Is used when the participants in the two groups are not the same people, nor connected to one another in a systematic way. Paired t-test - Answer-(Dependent group t test or correlated groups t test) Point biserial correlation - Answer- Analysis of Variance (ANOVA) - Answer-Is used to draw inferences about differences among population means. Between-group varaiance - Answer-Differences between groups Within-group variance - Answer-Differences between people in the groups F ratio - Answer-I Sum of squares - Answer-The sum of the square deviations around a mean. One-Way ANOVA - Answer-There is a single independent variable whole effect on a dependent variable is under study. Multifactorial ANOVA - Answer-When the effects of two or more independent variables on a dependent variable are studied simultaneously.