1) Which of the following is a normal distribution?  a) b) c) d) e) 2) Which of the following is a left-skew or a negative-skew of the normal distribution? a) b) c) d) e) 3) Which of the following is a Poisson distribution? (For fun) a) This isn't on the boards b) I don't know c) You never taught us that d) Don't worry about it e) What is this garbage? f) Don't select this answer because WordWall requires an incorrect option 4) Which of these is a bimodal distribution? a) b) c) d) e) 5) Pretend that you are doing a study about the range of systolic blood pressure found in medical staff at a clinic. You measure everyone's blood pressure for a month. You find that the values are normally distributed. Then one day there is a "polar vortex" and you have ridiculous snow. Two of the doctors get in car accidents on the way to work and two patients cause an accident in the parking lot. When you measure blood pressure that day you get a handful of abnormally high readings. When you add these to your data, what happens to the mean? a) Nothing, it remains constant b) It increases slightly, but stays almost the same c) It decreases slightly, but stays almost the same d) It increases significantly e) It decreases significantly 6) Pretend that you are doing a study about the range of systolic blood pressure found in medical staff at a clinic. You measure everyone's blood pressure for a month. You find that the values are normally distributed. Then one day there is a "polar vortex" and you have ridiculous snow. Two of the doctors get in car accidents on the way to work and two patients cause an accident in the parking lot. When you measure blood pressure that day you get a handful of abnormally high readings. When you add these to your data, what happens to the median of your data? a) Nothing, it remains constant b) It increases slightly, but stays close to the same value c) It decreases slightly, but stays close to the same value d) It increases significantly e) It decreases significantly 7) Pretend that you are doing a study about the range of systolic blood pressure found in medical staff at a clinic. You measure everyone's blood pressure for a month. You find that the values are normally distributed. Then one day there is a "polar vortex" and you have ridiculous snow. Two of the doctors get in car accidents on the way to work and two patients cause an accident in the parking lot. When you measure blood pressure that day you get a handful of abnormally high readings. When you add these to your data, what happens to the mode of your data?  a) Nothing, it remains constant b) It increases slightly, but stays close to the same value c) It decreases slightly, but stays close to the same value d) It increases significantly e) It decreases significantly 8) Pretend that you are doing a study about the range of systolic blood pressure found in medical staff at a clinic. You measure everyone's blood pressure for a month. You find that the values are normally distributed. Then one day there is a "polar vortex" and you have ridiculous snow. Two of the doctors get in car accidents on the way to work and two patients cause an accident in the parking lot. When you measure blood pressure that day you get a handful of abnormally high readings. When you add these to your data, what happens to the standard deviation of your data? a) Nothing, it remains constant b) It increases c) It decreases d) It turns blue e) Chicago 9) Pretend that you are doing a study about the range of systolic blood pressure found in medical staff at a clinic. You measure everyone's blood pressure for a month. You find that the values are normally distributed. Then one day there is a "polar vortex" and you have ridiculous snow. Two of the doctors get in car accidents on the way to work and two patients cause an accident in the parking lot. When you measure blood pressure that day you get a handful of abnormally high readings. When you add these to your data, what is most likely to happen to the standard error of your data? a) Nothing, it remains constant b) It increases c) It decreases d) It takes twice as much time e) Platypus 10) You do a study and 36 samples at your clinic. You calculate your mean, standard deviation, and standard error. Your friend performs the same study at his clinic and collects 28 samples. You decide to combine your datasets. The standard deviation stays the same, but your sample size is now increased to 64. What happens to your standard error? a) Nothing, because the standard deviation stayed the same b) It increases from 36 to 64 c) It increases from 6 to 8 d) It decreases because the sample size is in the denominator 11) You perform a study with 64 samples. You calculate the mean to be 144, the median to be 142, the mode to be 140 and the standard deviation to be 120. What is the standard error of your study? a) 10.95 b) 42 c) 8 d) 15 e) 120 12) You are doing a study to determine if regular exercise has an impact on anxiety. You have patients take a Hamilton Anxiety test (HAM-A) before the study and then again after three months of exercise. The output is a numerical score, where a higher score indicates greater anxiety. What is the null hypothesis of this study? a) Exercise will increase the HAM-A scores in participants b) Exercise will decrease the HAM-A scores in participants c) The HAM-A scores from before and after will not be different d) The HAM-A scores will be lower but this cannot be directly attributed to the exercise e) The HAM-A scores will be higher but this cannot be directly attributed to the exercise 13) You perform the study concerning anxiety with exercise (previous question) and the mean score from before the study was 8.2 and the mean score from after exercise was a 7.2. Which test would you use to determine if this difference is significant? a) ANOVA b) T-Test c) Linear Regression (Pearson) d) Chi-squared e) Fisher's exact test 14) You perform the study concerning anxiety with exercise (previous question) and the mean score from before the study was 8.2 and the mean score from after exercise was a 7.2. Your alpha level is 0.05 and your p-value is 0.054. Which statement is true?  a) You can reject the null hypothesis b) You can accept the null hypothesis c) You fail to reject the null hypothesis d) You do not have all of the information needed to answer this question. 15) You perform the study concerning anxiety with exercise (previous question) and the mean score from before the study was 8.2 and the mean score from after exercise was a 7.2. Your alpha level is 0.05 and your p-value is 0.048. Which statement is true?  a) You can reject the null hypothesis b) You can accept the null hypothesis c) You fail to reject the null hypothesis d) You do not have all of the information needed to answer this question. 16) You run the anxiety/exercise study and publish your results. Someone repeats your study and claims that you had reported a false positive. Which of the following statements are true according to their claim? (Select more than one) a) You had an alpha error b) You had a beta error c) You reported results as statistically significant but they were not really significant d) You did not have enough samples to find significance e) You falsified your data 17) You run the anxiety/exercise study and your results don't quite reach significance. Your boss tells you that you have a beta error. Which of the following statements are true according to your boss? (Select more than one) a) You had an alpha error b) You had a beta error (as stated directly in the question) c) You reported results as statistically significant but they were not really significant d) You did not have enough samples to find significance e) You falsified your data f) You did not have enough power 18) You run the study and get a p-value of 0.074. Your boss says you have a beta error and has you rerun the test with 5 times as many people. The results come back with a mean HAM-A value of 8.2 before the exercise and a mean HAM-A value of 8.1 after the exercise with a p-value of 0.048. Which of the following can be said of your experiment? a) You had an alpha error b) You had a beta error c) You achieved statistical significance d) You did not have enough samples to find significance e) You falsified your data f) You did not have enough power 19) You run the study and get a p-value of 0.074. Your boss says you have a beta error and has you rerun the test with 5 times as many people. The results come back with a mean HAM-A value of 8.2 before the exercise and a mean HAM-A value of 8.1 after the exercise with a p-value of 0.048. Which of the following biological interpretations can be assumed of your data? a) Exercise lowers anxiety as measured by the HAM-A scale b) This means nothing. Statistical significance does not mean biological significance and the difference between 8.1 and 8.2 probably doesn't mean anything. c) Your results are amazing and you should publish them in a top-tier journal d) You should repeat it again and see if you get an even better p-value e) You falsified your data f) You should make really fancy figures to emphasize just how much difference the exercise made 20) You do a study at your medical school to find out if sleep is related to performance on tests. You ask a group of students how many hours per night they slept during the week of each exam for a semester and then look at their final scores to determine if there is a relation. What is a good null hypothesis for this study?  a) Sleep and test scores are independent (unrelated) variables b) More sleep leads to higher scores on the exams c) More sleep means less studying and leads to lower scores on the exams d) Students that fall asleep in the exam tend to run out of time e) Students have no concept of how much sleep they need to maintain sanity 21) You perform the sleep hours vs test score study and the hours slept per night range from 4 to 11 with a median value of 6.5, and the test scores range from 37 to 100 with a median value of 73. Which test would you run to determine if there is a correlation between these variables? a) ANOVA b) T-test c) Chi-squared d) Fisher's exact test e) Linear regression (Pearson) 22) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.01. Your test's p-value is 0.0247. Which of the following is true about your result? a) You fail to reject the null hypothesis b) You accept the null hypothesis c) You reject the null hypothesis d) You need to write a new null hypothesis 23) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.01. Your test's p-value is 0.006. Which of the following is true about your result? a) You fail to reject the null hypothesis b) You accept the null hypothesis c) You reject the null hypothesis d) You need to write a new null hypothesis 24) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.01. Your test's p-value is 0.006. You reject the null hypothesis. Which of the following is true regarding the interpretation of the data? a) The number of hours spent sleeping and the test score are not independent, which means they are correlated to some degree. b) The number of hours spent sleeping and the test score are independent, which means they are not correlated. c) The number of hours slept per night during the week before the exam can be used to directly predict how students will perform on the exam. d) Scores on the exam can be used to directly determine how many hours students slept each night before the exam. 25) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.01. Your test's p-value is 0.006. Your R value is 0.24. Which of the following is true regarding the interpretation of the data? a) The correlation is negative, meaning that more hours slept tends to correlate with a lower score b) The correlation is positive, indicating that more hours slept correlates with a higher test score c) There is a significant correlation, but you cannot determine if it is a positive or a negative correlation d) There is no correlation. e) The correlation is strong enough that one variable can be used to almost entirely determine the other variable. 26) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.01. Your test's p-value is 0.006. Your R value is 0.24. Which of the following is the best biological interpretation of the data? a) Getting more sleep the week before the exam leads to higher brain function and therefore higher test scores b) More sleep the week before the exam means less time spent studying and therefore leads to lower test scores c) More time spent studying leads to higher test scores, indicating that students should plan to sleep more during the week of the exam d) The association is statistically significant, but the correlation is so low that nobody should base their plans off this data. e) The correlation is significant, but you cannot determine causality from a single study like this. 27) You run the sleep with test study's appropriate statistical test and you set your alpha level to 0.05. Your test's p-value is 0.056. Your boss tells you that he thinks you need more samples. Which of the following (select multiple) statements is your boss assuming are true? a) You have too much power b) You have a type 1 error c) You have a type 2 error d) You do not have enough power e) You have a beta error f) You have an alpha error 28) You do a study to determine if intravenous drug use is associated with contracting Hepatitis C in a large city. You look at clinical notes from individual when they got diagnosed with Hepatitis C and from individuals that attended the clinic for other reasons. You wanted to determine if individuals with Hepatitis C were more likely to have tried intravenous drugs. Which of the following is the null hypothesis of your study? a) Hepatitis C is correlated with intravenous drug use b) Intravenous drug use is associated with contracting Hepatitis C c) People with Hepatitis C are more likely to have tried intravenous drugs. d) People diagnosed with Hepatitis C and people at the clinic for other reasons do not have different rates of intravenous drug exposure.  e) People that use drugs intravenously are more likely to contract Hepatitis C 29) You are performing the Hepatitis C and intravenous drug use study from the previous question. Which of the following tests should you use? a) ANOVA b) T-test c) Linear correlation (Pearson) d) Proportion test (either Chi-squared or Fisher's exact) 30) You run the Hepatitis C and intravenous drug use study and learn that out of 1,000 people diagnosed with Hep C, 638 have previously tried intravenous drugs. However, of a random sample of 1,000 individuals that do not have Hep C, only 284 have ever tried intravenous drugs. The p-value for this test is 0.0012 and your alpha level is 0.05. Which of the following is true about your result? a) You can reject the null hypothesis b) You fail to reject the null hypothesis c) You accept the null hypothesis d) You need to write a new null hypothesis 31) You run the Hep C and intravenous drug use study and the p-value is 0.012 and your alpha level is 0.05. Your odds ratio is 4.4, indicating that individuals with Hep C are 4.4 times as likely to have tried intravenous drugs. Which of the following can you conclude from this study? a) This suggests that IV drug use is associated with contracting Hepatitis C, but you would need more experiments to conclude that is causes Hepatitis C. b) People that have Hepatitis C are more likely to try IV drugs in the future. c) People use IV drugs when they want Hepatitis C d) IV drugs prevent the spread of Hepatitis C e) Hepatitis C causes drug use 32) You run an experiment where you investigate the synergistic effect between two chemotherapy drugs. You test these drugs on four groups of mice. All mice have tumors. The four groups are control, Drug A only, Drug B only, and Drug C only. At the end of the study you weight the tumors and look at the mass of tumors from each animal in each group. Which test is the most appropriate test to use for this study? a) T-test b) ANOVA c) Chi-squared d) Fisher's exact test e) Linear regression 33) You perform the experiments to determine if there is a synergistic effect between two chemotherapy drugs as mentioned in the previous question. You already know that Drug A and Drug B are equally effective in reducing tumor volume and both are better than control, so you run an ANOVA between the three non-control groups. What is your null hypothesis for this test? a) The combination of Drug A and Drug B will be more effective than either group alone b) The combination of Drug A and Drug B will not be as effective than either group alone c) There is no difference in the mean reduction in tumor volume between the three groups d) Drug A will be more effective than Drug B or Drug B combined with Drug A 34) You perform the synergistic chemotherapy study and find the average reductions in tumor volume are 34% for Drug A, 39% for Drug B, and 54% for a combination of Drug A and Drug B. The p-value is 0.048 and the alpha level is 0.05. Which of the following can you conclude from this study? a) The p-value is significant, which means that at least two groups have a different mean b) Drug B is more effective than Drug A c) Drug A is more effective than Drug B d) Drug A and Drug B are both clearly toxic and the combined side effects are too dangerous to make the combination feasible for human studies

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