What is the major difference between a simple linear regression and a multiple linear regression? Group of answer choices multiple independent variables multiple dependent variables

Assignment Question

Question 10.5 pts When is the Pearson r correlation coefficient zero? Group of answer choices It is never zero when there is no linear correlation when there is a perfect positive correlation when there is a perfect negative correlation

Flag question: Question 2 Question 20.5 pts If the variance is 1, then the standard deviation is Group of answer choices 1 .5 2 0

Flag question: Question 3 Question 30.5 pts Which scenario best fits a simple regression? Group of answer choices A study comparing pretest and post-test scores on the same variable Using hours studied to predict test scores A longitudinal study with 3 time points

Flag question: Question 4 Question 40.5 pts Which significance test should be used to see if ADHD predicts grades in school? Group of answer choices single sample t-test independent samples t-test One-way ANOVA simple regression

Flag question: Question 5 Question 50.5 pts Which significance test should be used to see if time studying predicts your grade on this exam? Group of answer choices single sample t-test independent samples t-test simple regression Z-test

Flag question: Question 6 Question 60.5 pts We are testing a new treatment for anxiety. One group gets the treatment and the other group gets no treatment (Control group). Which significance test should we use? Group of answer choices single sample t-test dependent samples t-test independent samples t-test One-way ANOVA

Flag question: Question 7 Question 70.5 pts Use this scenario for the following three questions. A researcher created a short screening test for anxiety. A comparison was made with the gold standard for diagnosis of anxiety among 200 outpatients. Among the 50 outpatients found to be anxious according to the gold standard, 35 patients were positive for the test. Among 150 patients found not to be anxious according to the gold standard, 30 patients were found to be positive for the test. Which is correct to the nearest decimal place: Group of answer choices The sensitivity was 80% The specificity was 80% The positive predictive value was 70% The prevalence of anxiety on the screening test was 25%

Flag question: Question 8 Question 80.5 pts The following measures are identical whether the test is applied to general practice patients or to the psychiatric outpatients: Group of answer choices Prevalence of anxiety Sensitivity Specificity

Flag question: Question 9 Question 90.5 pts What was the negative predictive value to the nearest decimal place? Group of answer choices 88% 89% 88.9% 80%

Flag question: Question 10 Question 100.5 pts Use the following scenario for the next four questions. The table below shows the results from looking at the diagnostic accuracy of a new rapid test for HIV in 1,000 subjects, compared to the standard ELISA test. The rows of the table represent the test result and the columns the true disease status (as confirmed by ELISA). HIV+ HIV- Total Test + 90 100 190 Test – 10 800 810 100 900 1,000 What is the negative predictive value for the new rapid HIV test? Group of answer choices .90 .10 .99 .89

Flag question: Question 11 Question 110.5 pts What is the positive predictive value for the new rapid HIV test? Group of answer choices .47 .01 .10 .89 Flag question: Question 12 Question 120.5 pts What is the specificity of the new rapid HIV test? Group of answer choices .90 .10 .99 .89

Flag question: Question 13 Question 130.5 pts What is the sensitivity of the new rapid HIV test? Group of answer choices .90 .10 .99 .89

Flag question: Question 14 Question 140.5 pts Which scenario best fits a one-way ANOVA? Group of answer choices testing the difference between urban, suburban, and rural hospitals on nursing burnout? testing the difference between males and females on depression determining if there is a relationship between foot size and IQ scores predicting statistics exam scores based on hours spent studying for the exam

Flag question: Question 15 Question 150.5 pts What is the range of the following set of numbers? 4, 5, 6, 7 ,8, 9, 10, 100, 1000 Group of answer choices 1000 8 996 4

Flag question: Question 16 Question 160.5 pts What is the mean of the following set of numbers? 4, 5, 6, 7 ,8, 9, 10, 100, 1000 Group of answer choices 130.0 127.55 127.66 125.4

Flag question: Question 17 Question 170.5 pts What is the mode of the following set of numbers? 4, 5, 4, 7 ,8, 9, 10, 100, 1000 Group of answer choices 4 5 10 100

Flag question: Question 18 Question 180.5 pts Which significance test should be used to see if my treatment group did better on the exam than my control group across five different time points? Group of answer choices independent samples t-test dependent samples t-test one-way ANOVA repeated measures ANOVA

Flag question: Question 19 Question 190.5 pts A researcher tells you that she got a p calculated value of .04 from an inferential test she conducted. She asks you if her results are statistically significant. The most informed response would be: Group of answer choices Yes, because the probability of obtaining your sample statistic was less than .05. Yes, because your alpha level was greater than your obtained p calculated. No, because the probability of obtaining your sample statistic was greater than .05. No, because your alpha level was greater than your obtained p calculated. It depends, what did you set your probability of a Type I error to be?

Flag question: Question 20 Question 200.5 pts The scale of a Pearson r correlation coefficient is: Group of answer choices Nominal Interval Ordinal Ratio

Flag question: Question 21 Question 210.5 pts Which alpha level below corresponds to the most risk of Type I error? Group of answer choices Alpha = .10 Alpha = .05 Alpha = .01 Alpha = .001

Flag question: Question 22 Question 220.5 pts Which statement is NOT true regarding the slope of a regression equation? Group of answer choices The slope quantifies the steepness of the line. If the slope is negative, Y tends to decrease as X tends to decrease. If the slope is positive, Y tends to increase as X tends to increase. None of the above, all are true.

Flag question: Question 23 Question 230.5 pts A researcher is interested in the relation between number of years working for a particular company and loneliness at work. He surveyed 40 workers at this company and figured a correlation between these two variables of -.90, the correlation is considered a Group of answer choices Weak positive linear correlation. Weak negative linear correlation. Strong positive linear correlation. Strong negative linear correlation.

Flag question: Question 24 Question 240.5 pts Given r = .8 and a p calculated of .6, when we test the null hypothesis that r = 0, we can say that: Group of answer choices there is an 80% probability of obtaining at least r = .8 from any random sample, if the r should have been 0. here is a 60% probability of obtaining at least r = .8 from any random sample, if the r should have been 0. there is a 60% probability of not obtaining at least r = .8 from any random sample, if the r should have been 0. there is an 80% probability of not obtaining at least r = .8 from any random sample, if the r should have been 0.

Flag question: Question 25 Question 250.5 pts A Pearson r of .70 is how much stronger than a Pearson r of .00 in terms of shared variance between the two variables? Group of answer choices 30% 40% 49% 70% None of the above

Flag question: Question 26 Question 260.5 pts In hypothesis testing, if we found a statistically significant difference between the means of two groups, then we: Group of answer choices rejected the null. failed to reject the null. committed Type I error. committed Type II error.

Flag question: Question 27 Question 270.5 pts Dr. Marcela conducted a study on SAT and GRE scores and calculated the Pearson r correlation between these scores for a sample of graduate students. Which correlation coefficient is least likely to reflect the relationship between these variables? Group of answer choices -1.0 -0.1 1.4 1.0 None of the above, all are equally plausible

Flag question: Question 28 Question 280.5 pts In the equation Ŷ = a + bX, b is the symbol for the Group of answer choices correlation coefficient. regression coefficient. proportionate reduction in error. regression constant.

Flag question: Question 29 Question 290.5 pts You are interested in whether IQ is influenced by the amount of TV people watch. You place participants into one of three groups: 1) more than 8 hours of TV per week, 2) between 3 and 8 hours of TV per week, and 3) less than 3 hours of TV per week. You then administer an intelligence exam. You hypothesize that people who watch the least amount of TV will have the highest intelligence. Which type of test should you use? Group of answer choices single sample t-test dependent samples t-test independent samples t-test one-way ANOVA

Flag question: Question 30 Question 300.5 pts You are interested in whether type of music influences people’s stress levels. You assign participants to one of two groups: 1) rock music, or 2) ambient music. Each group then listens to rock or ambient (depending on assigned group) for 20 minutes, and then answers the Perceived Stress Scale. You hypothesize that people who listen to ambient music will have lower stress levels than those who listen to rock music. Which type of test should you use? Group of answer choices single sample t-test dependent samples t-test independent samples t-test one-way ANOVA

Flag question: Question 31 Question 310.5 pts A researcher believes that a new drug will improve the memory of patients with Alzheimer’s disease. He assigns participants to take the new drug three times per day for one month. He then assesses the memory of these patients and compares their scores with the scores of the population of patients with Alzheimer’s disease. He hypothesizes that patients who take the new drug will have significantly higher memory scores than the population of patients with Alzheimer’s disease who do not get the drug. Which type of test should he use Group of answer choices single sample t-test dependent samples t-test independent samples t-test one-way ANOVA

Flag question: Question 32 Question 320.5 pts A statistically significant result means that, given the assumptions of the test, you have a(n): Group of answer choices Replicable result Unlikely result Unimportant result

Flag question: Question 33 Question 330.5 pts Which of the following is an example of an alternative hypothesis? Group of answer choices Exercising 30 minutes a day for 2 weeks does not decrease heart rate by 10%. Taking 500mg of ibuprofen within 20 minutes of onset will decrease headache pain. Studying more than 5 hours for statistics final does not impact your grade. There is no difference between the mean self-esteem scores of men and women athletes at TWU.

Flag question: Question 34 Question 340.5 pts A researcher believes that a new drug will reduce the probability of an individual being depressed. He assigns participants to take the new drug three times per day for one month. He then assesses if the participants are depressed or not. He hypothesizes that patients who take the new drug will have a lower likely hood of being depressed. Which type of test should he use? Group of answer choices linear regression multiple regression one-way ANOVA logistic regression

Flag question: Question 35 Question 350.5 pts What is the major difference between a simple linear regression and a multiple linear regression? Group of answer choices multiple independent variables multiple dependent variables

Flag question: Question 36 Question 360.5 pts What scale of measurement does your independent variable need to be to conduct a logistic regression Group of answer choices nominal ordinal interval ratio A or B C or D

Flag question: Question 37 Question 370.5 pts A run chart is a __________ of values over time Group of answer choices box plot histogram normal distribution scatterplot

Flag question: Question 38 Question 380.5 pts Consider the process of “driving to school” with the measure being driving time. The variation cause by the effect of traffic signals is an example of: Group of answer choices common cause variation special cause variation random error being out-of-control none of the above

Flag question: Question 39 Question 390.5 pts A teacher who constructs a frequency table to summarize grades collected on the mathematics exam last week is using Group of answer choices a measure of central tendency. a descriiptive statistical method. an intuitive statistical method. an inferential statistical method.

Flag question: Question 40 Question 400.5 pts The length of time a person talks in a group discussion is an example of a(n) Group of answer choices transformed variable. categorical variable. continuous variable. extraneous variable.