Essentials Of Statistics For The Behavioral Sciences 5th Edition Frederick J Gravetter, Larry B. Wallnau - Solutions

Enhance your understanding of "Essentials Of Statistics For The Behavioral Sciences, 5th Edition" by Frederick J. Gravetter and Larry B. Wallnau with our comprehensive resources. Access the online answers key for detailed solutions and step-by-step answers to all solved problems. Our solution manual offers precise solutions in PDF format, perfect for clarifying complex questions and answers. Dive into the test bank for a variety of questions, and explore chapter solutions with our instructor manual. This textbook's resources are available for free download, ensuring you have the tools you need for success.

23. A researcher would like to evaluate the relationship between a person's age and his/her preference between two leading brands of cola. In a sample of 30 people, the researcher found that 1 5 out of 1 8 people who were over 30 years old preferred brand A and only 3 out of 12 people under 30
22. In a study similar to one conducted by Fallon and Rozin (1985), a psychologist prepared a set of silhouettes showing different female body shapes ranging from somewhat thin to somewhat heavy and asked a group of women to indicate which body figure they thought men would consider the most
21. Although the phenomenon is not well understood, it appears that people born during the winter months are slightly more likely to develop schizophrenia than people born at other times (Bradbury & Miller, 1985).The following hypothetical data represent a sample of 50 individuals diagnosed with
20. Apparently there is a huge amount of misunderstanding concerning how the process of visual perception works. Specifically, many people believe (incorrectly)that at least part of looking at things involves energy going out of the eyes rather than energy coming into the eyes. This
19. Darley and Latane (1968) conducted a study examining the factors that influence whether a person will try to help someone in need. Each participant was placed in a preexisting group of either 2 people. 3 people, or 6 people. The participants were led to believe that they were participating in
Cialdini, Reno, and Kallgren (1990) examined how people conform to norms concerning littering. The researchers wanted to determine whether a person's tendency to litter depended on the amount of litter already in the area. People were handed a handbill as they entered an amusement park. The
Research indicates that people who volunteer to participate in research studies tend to have higher intelligence than nonvolunteers. To test this phenomenon, a researcher obtains a sample of 200 high school students.The students are given a description of a psychological research study and asked
Is there a relationship between gender and the aggression content of dreams? Test with a — .01.16. Recent reports suggest that children who grow up with pets in the home tend to develop resistence to allergies.To test this phenomenon, a researcher interviews a sample of n = 120 college students.
Gender differences in dream content are well documented(see Winget & Kramer, 1979). Suppose a researcher studies aggression content in the dreams of men and women. Each participant reports his or her most recent dream. Then each dream is judged by a panel of experts to have low, medium, or high
The data from Problem 1 3 show no significant difference between the opinions for city residents and those who live in the suburbs. To construct the following data, we simply doubled the sample size from Problem 13 so that all of the individual frequencies are twice as big. Notice that the sample
A local county is considering a budget proposal that would allocate extra funding toward the renovation of city parks. A survey is conducted to measure public opinion concerning the proposal. A total of 150 individuals respond to the survey: 50 who live within the city limits and 100 from the
The observed frequencies are as follows:No heart disease Heart disease Type A Type B 32 18 128 22 50 150 160 40 Is there a relationship between personality and disorder?Test at the .05 level of significance.
12.Upper half Lower half 13.Book 1 Book 2 Book 3 18 30 12 34 10 16 60 60 40 Do the data indicate that the distribution of preferences for students in the upper half of the class is significantly different from the distribution for students in the lower half? Test at the .05 level of
11. In Problem 10, a professor asked students to rate three textbooks to determine whether there were any preferences among them. Although the data appear to indicate an overall preference for book 1 , the professor would like to know whether this opinion is shared by students with different levels
10. A psychology professor is trying to decide which textbook to use for next year's introductory class. To help make the decision, the professor asks the current students to review three texts and identify which one they prefer. The distribution of preferences for the current class is as
Are the data sufficient to conclude that the age distribution for jurors is significantly different from the distribution for the population of registered voters?Test with a — .05.
Do the data indicate that the distribution of accidents for the three age groups is significantly different from the distribution of drivers? Test with a = .05.A social psychologist suspects that people who serve on juries tend to be much older than citizens in the general population. Jurors are
8. Automobile insurance is much more expensive for teenage drivers than for older drivers. To justify this PROBLEMS 483 cost difference, insurance companies claim that the younger drivers are much more likely to be involved in costly accidents. To test this claim, a researcher obtains information
A professor in the psychology department would like to determine whether there has been a significant change in grading practices over the years. It is known that the overall grade distribution for the department in 1985 had 14% As, 26% Bs, 31% Cs, 19% Ds, and 10% Fs. A sample of n = 200 psychology
Suppose the researcher from the previous problem repeated the cola-preference study using twice as many students and obtaining observed frequencies that exactly doubled the original values. The resulting data are as follows:Brand A Brand B Brand C 56 28 36a. Use a chi-square test to determine
A researcher obtained a random sample of n = 60 students to determine whether there were any significant preferences among three leading brands of colas.Each student tasted all three brands and then selected his or her favorite. The resulting frequency distribution is as follows:Brand A Brand B
Do the data indicate any significant preferences among the three versions of the photograph? Test at the.05 level of significance.
The original photograph and the two modifications arc then shown to a sample of n = 150 college students, and each student is asked to select the "most beautiful"of the three faces. The distribution of responses was as follows:Original photo Eyes moved apart Eyes moved together
Do the data indicate any significant preferences among the four colors? Test at the .05 level of significance.A researcher is investigating the physical characteristics that influence whether or not a person's face is judged as beautiful. The researcher selects a photograph of a woman and then
4.38 28 24 A developmental psychologist would like to determine whether infants display any color preferences. A stimulus consisting of four color patches (red, green, blue, and yellow) is projected onto the ceiling above a crib.Infants are placed in the crib, one at a time, and the psychologist
2. A major snack-food company has started an advertising campaign claiming that it makes 'America's favorite potato chip." To test this claim, a researcher assembles a sample of 90 volunteers and asks each individual to taste the company's chips along with two other brands. Each individual is asked
1. Parametric tests (such as t or ANOVA) differ from nonparametric tests (such as chi-square) primarily in terms of the assumptions they require and the data they use. Explain these differences.
25. Find the regression equation for the following data:X y 3 12 84 18 2 12 1 8
23. For the following set of data, find the linear regression equation for predicting Y from X:X Y 92 9 4 7 6 3 X Y 1 2 4 7 3 5 2 1 5 14 3 7a. Compute the Pearson correlation.b. Find the linear regression equation for predicting Y from X.c. Use the regression equation to compute the predicted Y for
24. For the following set of data.Training No training 2 4 5 7 6 3 7 6a. Without doing any calculations, estimate the pointbiserial correlation for these data.b. Convert the data to a form suitable for the pointbiserial.and compute the correlation.
22. The data in Problem 2 1 showed a mean difference of 3 points between the training group and the no-training group (M = 8 versus M = 5). Because there is a 3-point difference, you would expect to find that quiz scores are related to training (there is a nonzero correlation).Now consider the
21. To test the effectiveness of a new studying strategy, a psychologist randomly divides a sample of 8 students into two groups, with n = 4 in each group. The students in one group receive training in the new studying strategy. Then all students are given 30 minutes to study a chapter from a
20. Problem 22 in Chapter 10 presented hypothetical data showing that elderly people who own dogs are significantly less likely to pay visits to their doctors than those who do not own pets. The independent-measures/ test produced t = 2.98 with df = 10 and a value of r2 = 0.47(47%).a. Convert the
19. The point-biserial correlation and the independentmeasures t test can both be used to evaluate the same set of data.a. What is measured by the correlation? What is measured by the t test?b. What factor can influence the outcome of the t test, but has no influence on the size of the correlation?
18. For the following data, X and Y are related by the equation Y = X*.X Y 1 1 2 8 3 27 4 64a. Sketch a graph showing the X and Y data points and describe the relationship.b. Compute the Pearson correlation for these data.c. Compute the Spearman correlation for these data.
Because there are no absolute right or wrong answers, these grades must be based on a judgment of quality.To demonstrate that these judgments actually are valid, an English instructor asked a colleague to rankorder a set of term papers. The ranks and the instructor's grades for these papers are as
16. Rank the following scores, and compute the Spearman correlation between X and Y:17.X Y 7 19 2 4 11 34 15 28 32 104 A common concern for students (and teachers) is the assignment of grades for essays or term papers.
15. What is the major distinction between the Pearson and Spearman correlations?
14. A psychologist would like to determine whether there is any consistent relationship between intelligence and creativity. A random sample of n = 18 people is obtained, and the psychologist administers a standardized IQ test and a creativity test to each individual.Using these data, the
13. A high school counselor would like to know whether there is a relationship between mathematical skill and verbal skill. A sample of n = 25 students is selected, and the counselor records achievement test scores in mathematics and English for each student. The Pearson correlation for this sample
12. Assuming a two-tailed test with a = .05, how large a correlation is needed to be statistically significant for each of the following samples?a. A sample of n = 15 individualsb. A sample of n = 30 individualsc. A sample of n = 92 individuals
The following hypothetical data are scores for married couples.Couple Wife Husband A 11 14 B 6 7 C 18 15 D 4 7 E 1 3 F 10 9 G 5 9 H 3 3a. Compute the correlation between the children and their birth parents.b. Compute the correlation between the children and their adoptive parents.c. Based on the
10. It is well known that similarity in attitudes, beliefs, and interests plays an important role in interpersonal attraction (see Byrne, 1971, for example). Thus, correlations for attitudes between married couples should be strong. Suppose a researcher developed a questionnaire that measures how
Correlation studies are often used to help determine whether certain characteristics are controlled more by genetic influences or by environmental influences.These studies often examine adopted children and compare their behaviors with the behaviors of their birth parents and their adoptive
11.Compute the Pearson correlation for these data, and determine whether or not there is a significant correlation between attitudes for husbands and wives. Set alpha at .05, two tails.
Researchers who measure reaction time for human participants often observe a relationship between the reaction time scores and the number of errors that the participants commit. This relationship is known as the speed-accuracy trade-off. The following data are from a reaction time study where the
8. In the following data, there are three scores (X, Y, and Z) for each of the n = 5 individuals:X Y Z 3 5 5 4 3 2 21 41 63 2 4 Sketch a graph showing the relationship between X and Y. Compute the Pearson correlation between X and Y.Sketch a graph showing the relationship between Y and Z. Compute
7. To measure the relationship between anxiety level and test performance, a psychologist obtains a sample of n = 6 college students from an introductory statistics course. The students are asked to come to the laboratory 15 minutes before the final exam. In the lab, the psychologist records
6.a. Compute the Pearson correlation for the following set of data:X Y 31 1 2 5 3 9 4 7b. Add 5 points to each X value, and compute the Pearson correlation again.c. When you add a constant to each score, what happens to 55 for X and Yl What happens to SP1 What happens to the correlation between X
5, you will see that the correlation measures the relationship between X and Y. These two problems use the same X and Y values, but they differ in the way X and Y are related.
5. For this problem, we have used the same X and Y values that appeared in Problem 4, but we have changed the X, Y pairings:X Y 1 6 2 8 4 2 53 4a. Sketch a graph showing these reorganized data.b. Estimate the Pearson correlation just by looking at your graph.c. Compute the Pearson correlation.
4. For the following set of data, X Y 12 2 4 6 5 8 3 4a. Sketch a graph showing the location of the five X, Y points.b. Just looking at your graph, estimate the value of the Pearson correlation.c. Compute the Pearson correlation for this data set.
3. For each of the following sets of scores, calculate SP using the definitional formula and then using the computational formula:Set 1 Set 2 X Y x y 1 2 3 5 3 2 6 1 5 3 4 2 7 5 7
2. What information is provided by the numerical value of the Pearson correlation?
1. What information is provided by the sign (+ or — ) of the Pearson correlation?
25. For the following set of data:a. Compute the cell means and place them in an A X B matrix.b. Using the cell means, row means, and column means, state whether or not you think there will be an interaction of factors A and B, a main effect for factor A, and a main effect for factor B. (See
24. Shrauger (1972) conducted an experiment that examined the effect of an audience on the performance of two different personality types. Hypothetical data from this experiment are as follows. The dependent variable is the number of errors made by each participant.High Self-esteem Low Alone With
23. A researcher conducted a two-factor research study using two levels of factor A and two levels of factor B with a separate sample of /; = 12 subjects in each of the four treatment conditions (cells). The following table summarizes the results of the analysis, but it is not complete. Fill in the
22. A researcher conducted a two-factor research study using two levels of factor A and three levels of factor B with a separate sample of n = 10 subjects in each of the six treatment conditions (cells). The following table summarizes the results of the analysis, but it is not complete. Fill in the
21. Most sports injuries are immediate and obvious, like a broken leg. However, some can be more subtle, like the neurological damage that may occur when soccer players repeatedly head a soccer ball. To examine long-term effects of repeated heading. Downs and Abwender (2002) examined two different
20. The following data were obtained from an independent-measures experiment using n = 5 subjects in each treatment condition:Factor B Factor A TSS 15 80 T55 570 IX2 T=25 55 = 90 7= 55 55= 80 1100a. Compute the means for each cell, and draw a graph showing the results of this experiment. Your graph
19., The following data are from a two-factor experiment with n = 10 subjects in each treatment condition (each cell):Factor B Factor A TSS 40 70 T= 30 55 = 73 T= 10 55 = 80 T= 20 55 = 65 IX2 = 588 Use a two-factor ANOVA with a = .05 to evaluate the main effects and the interaction.
18. The following matrix presents the results of a twofactor experiment with two levels of factor A, two levels of factor B, and n = 10 subjects in each treatment condition. Each value in the matrix is the mean score for the subjects in that treatment condition.Notice that one of the mean values is
17. Each of the following sets of data represent the outcome from a two-factor study evaluating males and females (factor A) and two different ages (factor B).For each set of data, determine whether the data indicate a main effect for factor A (overall mean difference between males and females); a
16. Briefly explain what happens during the second stage of the two-factor ANOVA.
15. The structure of a two-factor study can be presented as a matrix with one factor determining the rows and the second factor determining the columns. With this structure in mind, identify the three separate hypothesis tests that make up a two-factor ANOVA, and explain the purpose of each test.
14. The following summary table presents the results of an ANOVA from a repeated-measures experiment comparing four treatment conditions with a sample of n = 10 subjects. Fill in all missing values in the table.Source SS df MS Between treatments Within treatments Between subjects Error Total 10 12
13. A researcher uses a repeated-measures study to examine the effectiveness of a therapy procedure for treating depression. A sample of n = 10 depressed patients is obtained and each individual is given a depression test immediately before therapy, immediately after therapy, and once again 3
12. In Problem 1 1 the data show moderate differences from one person to another. In the following data, we have exaggerated the individual differences by adding 4 points to each score for participant B. Except for this change, the data are identical to the scores in Problem 1 1a. Keeping in mind
It has been demonstrated that when participants must memorize a list of words serially (in the order of presentation), words at the beginning and end of the list are remembered better than words in the middle. This observation has been called the serial-position effect.The following data represent
11.a. Use a repeated-measures analysis of variance with a = .05 to determine whether there are any significant differences among the three treatments.b. If the data were from an independent-measures study (three separate samples, each with n = 4), what value would be used for the denominator of the
10. The following data were obtained from a repeatedmeasures study comparing three treatment conditions.Treatment Subject I II III P A 6 8 10 24 G = 48 B 5 5 5 15 2X2 = 294 C 1 2 3 6 D 1 2 3 T = 12 T = 16 T = 20 55 = 26 55 = 30 SS = 38
9. The following data were obtained in a repeatedmeasures study using one sample of n = 4 individuals to compare three different treatments. Use an analysis of variance with a = .05 to determine whether there are any significant differences among the treatments.Treatment Person I II III A 4 3 8 N=
8. A researcher used an analysis of variance to evaluate the results from a single-factor repeated-measures experiment. The reported F-ratio was F(3, 48) = 5.80.a. How many different treatments were compared in this experiment?b. How many subjects participated in the experiment?
7. A researcher reports an F-ratio with df = 1, 38 from a repeated-measures experiment.a. How many treatment conditions were compared in this experiment?b. How many subjects participated in the experiment?
6. A researcher reports an F-ratio with df=2,24 for a repeated-measures ANOVA.a. How many treatment conditions were evaluated in this experiment?b. How many subjects participated in this experiment?
5. A researcher conducts a repeated-measures study using a sample of n = 15 participants to evaluate the differences among four treatment conditions. If the results are examined with an ANOVA, what are the Rvalues for the F-ratio?
4. A researcher conducts an experiment comparing three treatment conditions. The data consist of n = 20 scores for each treatment condition.a. If the researcher used an independent-measures design, then how many individuals were needed for the study and what are the df values for the F-ratio?'b. If
3. A researcher conducts a repeated-measures experiment using a sample of n = 12 subjects to evaluate the differences among three treatment conditions. If the results are examined with an ANOVA, what are the df values for the F-ratio?
2. The repeated-measures analysis of variance can be viewed as a two-stage process. What is the purpose for the second stage?
1. How does the denominator of the /-"-ratio (the error term) differ for a repeated-measures analysis of variance compared to an independent-measures ANOVA?
25. There have been a number of studies on the adjustment problems ("jet lag") people experience when traveling across time zones (see Moore-Ede, Sulzman,& Fuller, 1982). Jet lag always seems to be worse when traveling east. Consider this hypothetical study.A researcher examines how many days it
24. First-born children tend to develop language skills faster than their younger siblings. One possible explanation for this phenomenon is that first-borns have undivided attention from their parents. If this explanation is correct, then it is also reasonable that twins should show slower language
23. Use an analysis of variance with a = .05 to determine whether the following data provide evidence of any significant differences among the three treatments:Treatment Treatment 1 2 Treatment 377 = 4 77 = 5 77 = 6 N = 15 7* = 2 T= 10 T= 18 G = 30 55= 13 55 = 21 55 = 26 IX2 = 135
22. A clinical psychologist has noted that autistic children seem to respond to treatment better if they are in a familiar environment. To evaluate the influence of environment, the psychologist selects a group of 15 autistic children who are currently in treatment and randomly divides them into
21. A psychologist would like to examine the relative effectiveness of three therapy techniques for treating mild phobias. A sample of N = 15 individuals who display a moderate fear of spiders is obtained. These individuals are randomly assigned (with ;; = 5) to each of the three therapies. The
20. In the preceding problem the three sample means are close together and there are no significant mean differences.To construct the following data, we started with the scores in Problem 19 and then moved the individuals in the third sample farther away from the other tw o groups. Specifically, we
19. The following data are from an experiment comparing three treatment conditions with a separate sample of/; = 4 in each treatment.a. Use an ANOVA with a = .05 to determine whether there are any significant differences among the three treatments.b. Compute r\~ for these data.I II III 1 5 G = 36 4
18. A common science-fair project involves testing the effects of music on the growth of plants. For one of these projects, a sample of 24 newly sprouted bean plants is obtained. These plants are randomly assigned to four treatments, with n = 6 in each group. The four conditions are rock, heavy
17. A pharmaceutical company has developed a drug that is expected to reduce hunger. To test the drug, three samples of rats are selected with n = 12 in each sample.The first sample receives the drug every day. The second sample is given the drug once a week, and the third sample receives no drug
16. The following summary table presents the results of an ANOVA from an experiment comparing four treatment conditions with a sample of n = 10 in each treatment. Complete all missing values in the table.(Hint: Start with the df column.)Source S5 df MS Source SS df MS Between treatments Within
14. Then compute the average of the three sample variances and compare your result to A/Swi ,nin treatments that you obtained from the analysis of variance.
15. Like pooled variance (Chapter 10. page 251) the MS within treatments is an average of the sample variances.When the samples are all the same size (equal/is). A/5wlthin treatment- is exactly equal to the average of the sample variance. To demonstrate this fact, compute the variance for each of
14. A developmental psychologist is examining problemsolving ability for grade school children. Random samples of 5-year-old, 6-year-old, and 7-year-old children are obtained with n = 3 in each sample. Each child is given a standardized problem-solving task, and the psychologist records the number
13. The following data are constructed so that there is no variability inside any of the treatment conditions.a. Before you begin any calculations, predict what value should be obtained for S5within treatments- (Hint:How big are the differences within treatments?)b. Calculate 55totai and
12. The following data are constructed so that all three treatments have exactly the same mean, M = 4.a. Before you begin any calculations, predict what value should be obtained for 5Sbetween treatments-[flint: How big are the differences between treatments'ib. Calculate .S'.V,,,,.,, and 55wllh
11. The data from Problem 10 show significant differences between treatments. To construct the following data, we started with the numbers in Problem 10 but we increased the variance within each sample.Specifically, we kept the same means as in Problem 1 0. but we spread out the scores inside each
10.The following data were obtained in a study using three separate samples to compare three different treatments.a. Use an analysis of variance with a = .05 to determine whether there are any significant differences among the treatments.b. Compute the value for r\2 for these data.Treatment I II
9. The results from an independent-measures research study indicate that there are significant differences between treatments, F(2, 30) = 4.80, p < .05.a. How many treatments were compared in the study?b. How many individuals participated in the entire study?
8. A researcher reports an F-ratio with df = 3, 24 for an independent-measures research study.a. How many treatment conditions were compared in the study?b. How many subjects participated in the entire study?

Showing 1 - 100 of 5165

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Last

Essentials Of Statistics For The Behavioral Sciences 5th Edition Frederick J Gravetter, Larry B. Wallnau - Solutions

Step by Step Answers