professor compared differences in class grades between students in her class who a first years, sophomores, juniors, and seniors in college. Which statistical tests is appropriate for this study and why? (By using the decision tree). A. Z test B. Single sample t test C. Two independent samples t test D. Two related samples t test E. One way between subjects ANOVA F. Correlation

The Bureau of Labor Statistics reports that the official unemployment rate for Black people was 10.4% and 4.7% for White people in February 2015. Select all correct answers for this question. O The samples of white and black people are independent. The explanatory variable is the unemployment rate. The response variable is the unemployment rate. The response variable is race.

One study found a negative correlation between participant’s age and hours of sleep they got (as they got older, they slept less). Which additional fact would lead you to believe that the relationship between age and hours of sleep is one of causation and not correlation?     Jim is 63 and sleeps more than he did when he 47.     Josie is 40 and sleeps fewer hours than when she was 30.     The participants were randomly selected, the sample size was large, and the participants did not know the goal of the study.     Jennie sometimes has difficulty sleeping.

Which of these scenarios means that a pretest-posttest design with a non-equivalent control group is not suitable? Select all that apply. O a. All of the available participants will be receiving the intervention at the same time. O b. Authors want to examine for any trends in the data over time. O c. The participants were placed into the experimental and control groups by natural circumstances rather than random assignment. O d. Authors want to compare averages between two groups before and after the intervention using an ANOVA.

A researcher is studying the effects of the college experience on attitudes, values, and behaviors and is comparing random samples of freshman and seniors at the same university. Is there a significant difference in political ideology? (On this scale, 10 means "very conservative" and 1 means "very liberal") FRESHMAN SENIORSmean=5.23 mean=5.12s=1.78 s=1.07N=145 N=105

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 empathet The following data, representing random samples of 11 males and 11 females, are consistent with results reported in psychological studies. Boxplots show tha 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 μ₁ denote the mean empathy score for males and μ₂ denote the mean empathy score for females. Use the a=0.01 level and the critical value method with the table. 12 16 13 26 21 23 8 15 18 25 15 Males 21 23 15 26 25 28 24 16 19 20 23 Females Part 1 of 6 Send data to Excel State the appropriate null and alternate hypotheses. H₁ | M₁ = μ₂ H₁ :|µ₁ <µ₂ This is a…

A marketer is examining the effectiveness of color scheme on the willingness to subscribe to a user's social media account. She creates three different profiles using three different color schemes: red, blue, and green. Twenty participants are asked to evaluate how much they like each of the profiles using a scale of 1 (do not like) to 5 (like a lot). What statistical procedure should you use to analyze these data? O independent groups t test O correlated groups t test O One Way Between Subjects ANOVA O One Way Repeated Measures ANOVA

Restaurant Bill by GenderA study compared the cost of restaurant meals when people pay individually versus splitting the bill as a group. In the experiment half of the people were told they would each be responsible for individual meals costs and the other half were told the cost would be split equally among the six people at the table. In the study, the diners were also chosen so that half the people at each table were female and half were male. We can test for a difference in mean meal cost between females (n1=24, x¯1=44.46, s¯1=15.48) and males (n2=24, x¯2=43.75, s2=14.81).Let group 1 and group 2 be the meal costs for females and males, respectively.   state the null and alternative hypotheses calculate the relevant test statistic find the p-value

The results of a random sample of students by type of school and their attitudes on safety steps taken by the school staff are shown in the table below.  At the 5% significance level, can you conclude that attitudes about safety steps taken by the school staff are related to the type of school?    School staff has  School Type  Taken all steps for  student safety  Taken some steps for  student safety  Public  40  51  Private  64  34

A. For which data set is the sample correlation coefficient r closest to −1? B. For which data set is the sample correlation coefficient r closest to 0? C. For which data set is the sample correlation coefficient r equal to 1?