STATS-302 Final Exam Practice Questions and Answers

STATS-302 Final Exam Practice Questions and Answers I wanted to study the proportion of TAMU students that like math, so I stood in front of the math building and asked every fifth student that walked in if they liked math or not. What kind of sample is this, and why might it be problematic? Simple random sample; The students who enter the math building are a random sample of students that attend the university. Thus, your conclusion would accurately estimate the proportion of TAMU students who like math. Convenience sample; The students who are entering the math building are more likely to be math majors that like math. Thus, your conclusion would overestimate the true proportion of TAMU students who like math. Cluster random sample; The students who dislike math are more likely to ignore you out of embarrassment. Thus, your conclusion would overestimate the true proportion of TAMU students who like math. Convenience sample; The students who are on campus in the - ANSWER-Convenience sample; The students who are entering the math building are more likely to be math majors that like math. Thus, your conclusion would overestimate the true proportion of TAMU students who like math. Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024 Copyright ©Stuvia International BV Page 2/28 In a public health study on the effects of consumption of fruits and vegetables on psychological well- being in young adults, participants were randomly assigned to three groups: (1) diet-as-usual, (2) an ecological momentary intervention involving text message reminders to increase their fruits and vegetable consumption plus a voucher to purchase them, or (3) a fruit and vegetable intervention in which participants were given two additional daily servings of fresh fruits and vegetables to consume on top of their normal diet. Participants were asked to take a nightly survey on their smartphones. Participants were student volunteers at the University of Otago, New Zealand. At the end of the 14-day study, only participants in the third group showed improvements to their psychological well-being across the 14-days relative to the other groups. Does the sample of participants have any sampling bias? Yes, the sample incur - ANSWER-Yes, the sample incurs voluntary response bias. In a study on voter behavior in Texas, the sample is chosen by first dividing the population into voting precincts. Several precincts are then randomly chosen and all voters within the chosen precincts are included in the sample. What form of sampling is this? Stratified Sampling Simple Random Sampling Multistage Clustered Sampling Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024 Copyright ©Stuvia International BV Page 3/28 Cluster Sampling - ANSWER-Cluster Sampling Suppose that a researcher evaluates her research claim that the average systolic blood pressure for adults in age 20-60 is higher than 120 which has been used as a guideline as a normal systolic blood pressure for decades. In her study, the average blood pressure of 200 randomly selected individuals who did not have any health issues was 123.6. In this study, the average blood pressure of adults that she wanted to investigate was ______, and the average blood pressure of 200 individuals is ________. Fill in the blank. - ANSWER-parameter; sample statistic Donny is working with an association of local dentists to better understand the dental habits of their city. He takes a survey of residents and asks them their age, gender, income, educational level, insurance status, how many times a day they brush their teeth, and how many times a year they visit the dentist. Educational level is collected by asking what is the highest level completed: elementary school, middle school, high school, college, or postgraduate study. As specifically as possible, what type of variable is educational level? - ANSWER-Categorical - Ordinal A researcher wants to determine if a new exercise program helps people lose weight. She recruits over 1200 subjects (her statistician determined this number from sample size calculations) and randomly assigns them to either participate in the new exercise program or no exercise program. She tells those in the new program group to exercise 3 times a week and tells those in the no exercise group that they should not exercise for the duration of the study. Based on this information, which of the following principles of experimental design is not present in this study? - ANSWER-Blinding Copyright © KAYLIN 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH NOVEMBER, 2024 Copyright ©Stuvia International BV Page 4/28 A researcher wants to determine if a new flu vaccine protects people from the flu better than the current vaccine. He has 100 subjects for his study. He believes that sex will affect how well the vaccine works, so within these 100 subjects, splits them up into males (48 subjects) and females (52 subjects). Within each sex, he randomly assigns half of the subjects to get the new flu vaccine and the other half to get the current flu vaccine. What type of study design is this? - ANSWER-Experimental Study: Block Design Taylor Swift is interested in learning what proportion of her fans watched her premiere Betty live at the ACM Awards on September 16, 2020. She takes a simple random sample of 500 fans and asks them. Of the 500 fans, 475 of them (95%) respond that they watched her perform. What is the statistic and what is its value? The statistic is the proportion of all Taylor Swift fans who watched the performance, which is unknown. The statistic is the proportion of the sampled Taylor Swift fans who