STA 270 -FINAL REVIEW STUDY GUIDE SOLUTIONS

STA 270 -FINAL REVIEW STUDY GUIDE SOLUTIONS Parameter - ANSWER-A value that describes an aspect (mean, proportion, correlation) of the population Statistic - ANSWER-a numerical measurement describing some characteristic of a sample. This value is computed from data in a sample. Random distribution - ANSWER-statistical distribution in which the location of members in a population is totally random, location of each individual is determined by chance/probability Statistical inference - ANSWER-The process of using data obtained from a sample to make estimates or test hypotheses about the characteristics of a population. Population - ANSWER-An entire mass of individuals from where a certain sample is taken explanatory variable - ANSWER-A variable that helps explain or influences changes in a response variable. Independent variable (x- axis) response variable - ANSWER-A variable that measures an outcome of a study. Dependent variable (y-axis) bootstrap sample - ANSWER-a random sample taken with replacement from the original sample, of the same size as the original sample bootstrap statistic - ANSWER-the statistic computed on a bootstrap sample Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024 Copyright ©Stuvia International BV Page 2/12 bootstrap distribution - ANSWER-The distribution of estimates calculated from each of the bootstrap re-samples taken from the original sample one dot on the bootstrap distribution = one sample statistic Confidence Interval (CI) - ANSWER-A range of values, calculated from the sample observations, that is believed, with a particular probability, to contain the true value of a population parameter. A 95% confidence interval, for example, implies that were the estimation process repeated again and again, then 95% of the calculated intervals would be expected to contain the true parameter value. Note that the stated probability level refers to properties of the interval and not to the parameter itself which is not considered a random variable. Hypothesis tests - ANSWER-use known distribution to determine whether null hypothesis can be rejected or otherwise correlation - ANSWER-measure of strength and direction of linear assoc b/w 2 considered variables Randomized comparative experiment - ANSWER-an experiment that uses both comparison of two or more treatments and random assignment of subjects to treatments matched pairs experiment - ANSWER-each case gets both treatments in random order and we examine individual differences in the response variable between the two treatments Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024 Copyright ©Stuvia International BV Page 3/12 Very useful to understand how the response varies significantly from a case to case. Paired data - ANSWER-2 measurements on each case, which leads to comparison of each case under different treatments. Why paired data? 1. Lower Std Deviation 2. Lower Type 2 error 3. Lower Margin of Error Standard Deviation (SD) - ANSWER-A measure of the variability of a data set, calculated as the square root of the variance (V). Standard error - ANSWER-An estimate of the standard deviation of the sampling distribution of a statistic. p value - ANSWER-Proportion of samples (when null = true) that gives statistics as extreme or more extreme as the observed sample statistics z score - ANSWER-a measure of how many standard d