The paper “Mood Food: Chocolate and Depressive Symptoms in a Cross-Sectional Analysis” (Archives of Internal Medicine [2010]: 699–703) describes a study that investigated the relationship between depression and chocolate consumption. Participants in the study were 931 adults who were not currently taking medication for depression. These participants were screened for depression using a widely used screening test. The participants were then divided into two samples based on the score on the screening test. One sample consisted of people who screened positive for depression, and the other sample consisted of people who did not screen positive for depression. Each of the study participants also completed a food frequency survey.
The researchers believed that the two samples were representative of the two populations of interest—adults who would screen positive for depression and adults who would not screen positive. The paper reported that the
Estimate the difference in the mean number of servings of chocolate per month in the population of people who would screen positive for depression and the mean number of chocolate servings per month in the population of people who would not screen positive for depression. Use a confidence level of 90% and be sure to interpret the interval in context.
Trending nowThis is a popular solution!
Chapter 11 Solutions
Introduction to Statistics and Data Analysis
- Dr. Ngo would like to know whether there is a relationship between the number of minutes per day that a person spends in prayer or quiet meditation and the degree of conflict that they have in their interpersonal relationships. He asks participants to complete an assessment of interpersonal conflict, with scores ranging from 1 (very low interpersonal conflict) to 50 (very high interpersonal conflict). He collects data from a random sample of 10 participants. The data is as follows: Participant Minutes in Prayer/Meditation Conflict in Relationships 1 3 25 2 30 14 3 0 29 4 23 21 5 5 32 6 16 6 7 0 43 8 18 12 9 7 37 10 27 19 Using SPSS, conduct the appropriate analysis. Interpret and report the results of your analysis in APA style.arrow_forwardA particular paper described a study of children who were underweight or normal weight at age 2. Children in the sample were classified according to the number of sweet drinks consumed per day and whether or not the child was overweight one year after the study began. Is there evidence of an association between whether or not children are overweight after one year and the number of sweet drinks consumed? Assume that it is reasonable to regard the sample of children in this study as representative of 2 to 3 years old children and then test the appropriate hypotheses using a .05 significance level. (Round your answer to two decimal places.) Number of Sweet Overweight? Drinks Consumed per Day Yes No 22 930 1 73 2071 2 56 1681 3 or More 102 3389 x2 = | P-value interval Op< 0.001 O 0.001 s p < 0.01 O 0.01 sp < 0.05 O 0.05 sp < 0.10 Op2 0.10 There is --Select--- v to conclude that there is an association between whether or not children are overweight after one year and the number of sweet…arrow_forwardConsider an experiment to determine the effects of alcohol and marijuana on driving. Five randomly selected subjects are given alcohol to produce legal drunkenness and then are given a simulated driving test (scored from a top score of 10 to a bottom score of 0). Five different randomly selected subjects are given marijuana and then the same driving test. Finally, a control group of five subjects is tested for driving while sober. The driving test scores and the One-Way ANOVA table for these data are shown below. Test the hypothesis that there is a difference among the means of the three groups at 1% significance level. Alcohol Drugs Control 3 2 8 4 6 7 2 4 8 1 4 5 3 3 6 The following is the summary statistics for the table above generated from an Excel one-way ANOVA analysis: ANOVA SS df MS F P-value Between Groups 46.800 2 23.400 13.500 0.000848594 Within Groups 20.800 12 1.733 Total 67.600 14 Based on the Excel output, does there appear to be a…arrow_forward
- 3. A researcher was interested in the effects of a drug on depression. Subjects were randomly assigned to one of the three groups. Subjects in the control group received a placebo and the subjects in the two treatment groups received either a 0.2 mg or a 0.4 mg dosage of the drug. After several weeks of drug (or placebo) treatment, the researcher measured the subjects' level of depression (a low score indicating greater depression) The following data were obtained. Placebo 0.2 mg 0.4 mg 12 11 12 10 9. 14 11 11 17 13 13 16 15 7 16 12 Mean of X = 10 14 12 S^2 = 5.6 8.4 Using 5% of significance, test the hypothesis that the three groups differ in their effectiveness.arrow_forwardOne study of cell phones and the risk of brain cancer looked at a group of 469 people who have brain cancer. The investigators then asked about the use of cell phones. Result: “Our data suggest that the use of hand- held cellular phones is not associated with risk of brain cancer. B . Based on this study, can you determine that cellular use does not CAUSE brain cancer? Why or why not?arrow_forwardThe National Highway traffic Safety Administration requires each U.S. state to carry out an observational study to assess the level of seat belt use in the state. One report summarized data from a study done in a certain state. The proportions in the accompanying table are based on observations of over 25,000 drivers and passengers. Uses Seatbelt Does Not Use Seat Belt Male 0.425 0.075 Female 0.452 0.048 Assume that these proportions are representative of adults in this state and that an adult from this state is selected at random. (a) What is the probability that the selected adult uses a seat belt? (b) What is the probability that the selected adult uses a seat belt given that the individual selected is male?arrow_forward
- Thanh Nguy.. Empathy: The Interpersonal Reactivity Index is a survey designed to assess four different types of empathy. One type of empathy, called Empathetic Concern, measures the tendency to feel sympathy and compassion for people who are less fortunate. The index ranges from 0 (less empathetic) to 28 (more empathetic). The following data, representing random samples of 12 males and 12 females, are consistent with results reported in psychological studies. Boxplots show that it is reasonable to assume that the populations are approximately normal. Can you conclude that the mean empathy score for men is less than the mean empathy score for women? Let u, denote the mean empathy score for men. Use the a = 0.01 level and the P-value method with the TI-84 Plus calculator. Males 20 12 16 13 26 21 23 15 18 25 15 Females 22 20 26 25 28 24 16 19 20 23 21 23 Send data to Excel Part 1 of 4 State the null and alternate hypotheses. i = ':°H i 'i:'H test. The hypothesis test is a two-tailed Part:…arrow_forwardA sample survey by Comcast asked a random sample of customers about use of the Internet and about the type of community they lived in. Here are the results: Internet Users: Rural: 433 Suburban: 1072 Urban: 536 Nonusers: Rural: 463 Suburban: 627 Urban: 388 Is there a relationship between Internet use and community type? Give statistical evidence to support your findings.arrow_forwardWe are interested in analysing the effect of the lockout laws introduced in some areas of the Sydney CBD and nearby surrounds on the number of alcohol-related violent incidents. Suppose we have two samples of data on the number of violent incidents in a number of local areas of the Sydney CBD and nearby surrounds. Pubs, hotels and clubs located in a subset of these areas became subject to the lockout laws when they were introduced in 2014. The first sample is from 2010 before the introduction of the lockout laws, and the second is from 2015 after the introduction of the law. The hypothesis we wish to test is that the introduction of the lockout laws reduces violent incidents in the areas in which the lockout laws were put in place. We use a difference-in-difference model on the pooled data from 2010 and 2015. We find the following results: viol_inc hat = 33.21 (5.29) + 12.43lockout (7.01) – 4.19Yr2015 (2.98) – 3.32 (lockout x Yr2015) (1.85) N = 181, R^2 = 0.128 Where: viol_incis the…arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillCollege Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage LearningBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt