Test bank for statistics for the behavioral sciences 9th edition by gravetter download

Test Bank for Statistics for the Behavioral Sciences 9th Edition by Gravetter Chapter 1: Introduction to Statistics Chapter Outline 1.1 Statistics, Science, and Observation Definitions of Statistics 1.2 Populations and Samples What are They? Variables and Data Parameters and Statistics Descriptive and Inferential Statistical Methods Statistics in the Context of Research 1.3 Data Structures, Research Methods, and Statistics Individual Variables Relationships between Variables The Experimental Method Nonexperimental Methods: Nonequivalent Groups and Pre-Post Studies Data Structures and Statistical Methods 1.4 Variables and Measurement Constructs and Operational Definitions Discrete and Continuous Variables Scales of Measurement The Nominal Scale The Ordinal Scale The Interval and Ratio Scales Statistics and Scales of Measurement 1.5 Statistical Notation Summation Notation Learning Objectives and Chapter Summary Instructor Notes - Chapter - page 1 Students should be familiar with the terminology and special notation of statistical analysis The terminology consists of: Statistical Terms population sample parameter statistic descriptive statistics inferential statistics sampling error Measurement Terms operational definition nominal ordinal interval ratio discrete variable continuous variable real limits Research Terms correlational method experimental method independent variable dependent variable nonexperimental method quasi-independent variable Figure 1.1 is useful for introducing the concepts of population and sample, and the related concepts of parameter and statistic The same figure also helps differentiate descriptive statistics that focus on the sample data and inferential statistics that are used to generalize from samples to populations Students should learn how statistical techniques fit into the general process of science Although the concept of sampling error is not critical at this time in the course, it is a useful way to introduce and justify the need for inferential statistics Figure 1.2 is a simple demonstration of the concept that sample statistics are representative but not identical to the corresponding population parameters, and that two different samples will tend to have different statistics The idea that differences can occur just by chance is the important concept After the concept of sampling error is established, Figure 1.3 shows the overall research process and identifies where descriptive statistics are used and where inferential statistics are used Statistical techniques are used near the end of the research process, after the researcher has obtained research results and needs to organize, summarize and interpret the data Chapter includes discussion of two aspects of research that precede statistics: (1) the process of measurement, and (2) the idea that measurements take place in the context of a research study The discussion includes the different scales of measurement and the information they provide, as well as an introduction to continuous and discrete variables Research studies are described in terms of the kinds of data they produce: correlational studies that produce data suitable for computing correlations (see Figure 1.4), and experimental studies that produce groups of scores to be compared, usually looking for mean differences (see Figure 1.6) Other types of research (non-experimental) that also involve comparing groups of scores are also discussed (see Figure 1.7) Instructor Notes - Chapter - page Students should learn the notation, particularly the summation notation, that will be used throughout the rest of the book There are three key concepts important to using summation notation: Summation is a mathematical operation, just like addition or multiplication, and the different mathematical operations must be performed in the correct order (see Order of Mathematical Operations, page 25) In statistics, mathematical operations usually apply to a set of scores that can be presented as a column of numbers Each operation, except for summation, creates a new column of numbers Summation, calculates the sum for the column Other Lecture Suggestions Early in the first class I acknowledge that a Most students are not there by choice (No one picked Statistics as an elective because it looked like a fun class.) b Many students have some anxiety about the course However, I also try to reassure them that the class will probably be easier and more enjoyable (less painful) than they would predict, provided they follow a few simple rules: a Keep Up In statistics, each bit of new material builds on the previous material As long as you have mastered the old material, then the new stuff is just one small step forward On the other hand, if you not know the old material, then the new stuff is totally incomprehensible (For example, try reading Chapter 10 on the first day of class It will make no sense at all However, by the time we get to Chapter 10, you will have enough background to understand it.) Keeping up means coming to class, asking questions, and doing homework on a regular basis If you are getting lost, then get help immediately b Test Yourself It is very easy to sit in class and watch an instructor work through examples Also, it is very easy to complete homework assignments if you can look back at example problems in the book Neither activity means that you really know the material For each chapter, try one or two of the end-of-chapter problems without looking back at the examples in the book or checking your notes Can you really the problems on your own? If not, pay attention to where you get stuck in the problem, so you will know exactly what you still need to learn Give students a list of variables, for example items from a survey (age, gender, education level, income, occupation) and ask students to identify the scale of measurement most likely to be used and whether the variable is discrete or continuous Instructor Notes - Chapter - page 3 Describe a non-experimental or correlational study and have students identify reasons that you cannot make a cause-and-effect conclusion from the results For example, a researcher finds that children in the local school who regularly eat a nutritious breakfast have higher grades than students who not eat a nutritious breakfast Does this mean that a nutritious breakfast causes higher grades For example, a researcher finds that employees who regularly use the company’s new fitness center have fewer sick days than employees who not use the center Does this mean that using the fitness center causes people to be healthier? In either case, describe how the study could be made into an experiment by a beginning with equivalent groups (random assignment) b manipulating the independent variable (this introduces the ethical question of forcing people to eat a nutritious breakfast) c controlling other variables (the rest of the children’s diet) After introducing some basic applications of summation notation, present a simple list of scores (1, 3, 5, 4) and a relatively complex expression containing summation notation, for example, Σ(X – 1) Ask the students to compute the answer You are likely to obtain several different responses Note that this is not a democratic process - the most popular answer is not necessarily correct There is only one correct answer because there is only one correct sequence for performing the calculations Have the class identify the step by step sequence of operations specified by the expression (First, subtract from each of the scores Second, square the resulting values Third, sum the squared numbers.) Then apply the steps, one by one, to compute the answer As a variation, present a list of steps and ask students to write the mathematical expression corresponding to the series of steps Instructor Notes - Chapter - page Exam Items for Chapter Multiple-Choice Questions Note: Questions identified with (www) are available to students as a practice quiz on the cengage.com/psychology/gravetter website A researcher uses an anonymous survey to investigate the study habits of American college students The entire group of American college students is an example of a(n) _ a sample b statistic c population d parameter A researcher uses an anonymous survey to investigate the study habits of American college students Based on the set of 56 surveys that were completed and returned, the researcher finds that these students spend an average of 4.1 hours each week working on course material outside of class For this study, the set of 56 students who returned surveys is an example of a(n) _ a parameter b statistic c population d sample (www) A researcher uses an anonymous survey to investigate the study habits of American college students Based on the set of 56 surveys that were completed and returned, the researcher finds that these students spend an average of 4.1 hours each week working on course material outside of class For this study, the average of 4.1 hours is an example of a(n) _ a parameter b statistic c population d sample A researcher is interested in the eating behavior of rats and selects a group of 25 rats to be tested in a research study The group of 25 rats is an example of a a sample b statistic c population d parameter Instructor Notes - Chapter - page 5 A researcher is curious about the average monthly cell phone bill for high school students in the state of Florida If this average could be obtained, it would be an example of a a sample b statistic c population d parameter (www) Although a research study is typically conducted with a relatively small group of participants known as a _, most researchers hope to generalize their results to a much larger group known as a _ a sample, population b statistic, sample c population, sample d parameter, population The relationship between a statistic and a parameter is the same as the relationship between a a sample and a population b a statistic and a parameter c a parameter and a population d descriptive statistics and inferential statistics (www) Statistical methods that organize, summarize, or simplify data are called _ a parameters b statistics c descriptive statistics d inferential statistics A characteristic, usually a numerical value, that describes a sample is called a _ a parameter b statistic c variable d constant 10 A researcher records the change in weight (gain or lost) during the first semester of college for each individual in a group of 25 freshmen, and calculates the average change in weight The average is an example of a _ a parameter b statistic c variable d constant Instructor Notes - Chapter - page 11 The average verbal SAT score for the entire class of entering freshmen is 530 However, if you select a sample of 20 freshmen and compute their average verbal SAT score you probably will not get exactly 530 What statistical concept is used to explain the natural difference that exists between a sample mean and the corresponding population mean? a statistical error b inferential error c sampling error d parametric error 12 A researcher conducts an experiment to determine whether moderate doses of St Johns Wort have any effect of memory for college students For this study, what is the independent variable? a the amount of St Johns Wort given to each participant b the memory score for each participant c the group of college students d cannot answer without more information 13 (www) A recent study reports that elementary school students who were given a nutritious breakfast each morning had higher test scores than students who did not receive the breakfast For this study, what is the independent variable? a the students who were given the nutritious breakfast b the students who were not given the nutritious breakfast c whether or not a breakfast was given to the students d the test scores for the students 14 In a correlational study a variable is measured and groups are compared b variables are measured and groups are compared c variable is measured and there is only group of participants d variables are measured and there is only group of participants 15 In an experimental study a variable is measured and groups are compared b variables are measured and groups are compared c variable is measured and there is only group of participants d variables are measured and there is only group of participants 16 For a research study comparing attitude scores for males and females, participant gender is an example of what kind of variable? a an independent variable b a dependent variable c a quasi-independent variable d a quasi-dependent variable Instructor Notes - Chapter - page 17 For an experiment comparing two methods for teaching social skill training to autistic children, the independent variable is _ and the dependent variable is _ a teaching methods, the autistic children b the autistic children, the social skills that are learned c the social skills that are learned, the autistic children d teaching methods, the social skills that are learned 18 Which of the following is an example of a discrete variable? a the age of each student in a psychology class b the gender of each student in a psychology class c the amount of time to solve a problem d the amount of weight gained for each freshman at a local college 19 (www) Which of the following is an example of a continuous variable? a the gender of each student in a psychology class b the number of males in each class offered by the college c the amount of time to solve a problem d number of children in a family 20 If it is impossible to divide the existing categories of a variable, then it is an example of a _ variable a independent b dependent c discrete d continuous 21 (www) Using letter grades (A, B, C, D, and E) to classify student performance on an exam is an example of measurement on a(n) _ scale of measurement a nominal b ordinal c interval d ratio st nd 22 Determining the class standing (1 , , and so on) for the graduating seniors at a high school would involve measurement on a(n) _ scale of measurement a nominal b ordinal c interval d ratio Instructor Notes - Chapter - page 23 (www) What additional information is obtained by measuring two individuals on an interval scale compared to a ordinal scale? a whether the measurements are the same or different b the direction of the difference c the size of the difference d none of the other options is correct 24 Determining a person's reaction time (in milliseconds) would involve measurement on a(n) _ scale of measurement a nominal b ordinal c interval d ratio 25 After measuring two individuals, a researcher can say that Tom’s score is points higher than Bill’s The measurements must come from a(n) _ scale a nominal b ordinal c interval d interval or ratio 26 (www) What is the first step to be performed in the following mathematical expression? (ΣX) a Square each score b Add the scores c Add the squared scores d Square the sum of the scores 27 What is the final step to be performed in the following mathematical expression? (ΣX) ? a Square each score b Add the scores c Add the squared scores d Square the sum of the scores 28 What is the final step to be performed when computing Σ(X – 2) ? a square each value b subtract points from each score c sum the squared values 2 d subtract from each X value Instructor Notes - Chapter - page 29 What is the value of (ΣX) for the following scores? Scores: 1, 5, a 10 b 16 c 30 d 64 30 What is the value of ΣX for the following scores? a 14 b 21 Scores: 1, 0, 2, c 28 d 49 31 What is the value of ΣX + for the following scores? a b 10 Scores: 1, 0, 2, c 11 d 14 32 (www) What is the value of Σ(X + 1) for the following scores? a b Scores: 1, 0, 1, c d 10 33 What is the value of Σ(X – 1) for the following scores? a 10 b 16 Scores: 1, 2, 1, c 36 d 49 34 What is the value of (ΣX) for the following scores? a 14 b 21 Scores: 1, 0, 2, c 28 d 49 35 What is the value of ΣX + for the following scores? Scores: 1, 6, a 10 b 11 c 13 d 16 Instructor Notes - Chapter - page 10 36 What is the value of Σ(X + 1) for the following scores? Scores: 2, 4, a 10 b 11 c 13 d 16 37 What is the value of Σ(X – 2) for the following scores? Scores: 2, 3, a b c d 10 38 (www) What is the value of Σ(X – ) for the following scores? Scores: 2, 3, a b 10 c 16 d 36 39 You are instructed to subtract four points from each score and find the sum of the resulting values How would this set of instructions be expressed in summation notation? a ΣX – b Σ (X – 4) c – ΣX d Σ(4 – X) 40 You are instructed to subtract four points from each score, square the resulting value, and find the sum of the squared numbers How would this set of instructions be expressed in summation notation? a ΣX – b (ΣX – 4) c Σ(X – 4) 2 d ΣX – True/False Questions 41 Using the average score to describe a sample is an example of inferential statistics 42 A researcher is interested in the average income for registered voters in the United States The entire group of registered voters is an example of a population 43 The average score for a population is an example of a statistic Instructor Notes - Chapter - page 11 44 A researcher interested in vocabulary development obtains a sample of 3-year-old children to participate in a research study The average score for the group of 20 is an example of a parameter 45 The goal for an experiment is to demonstrate that changes in one variable are responsible for causing changes in a second variable 46 An experimental research study typically involves measuring two scores for each individual in one group of participants 47 A correlational study typically uses only one group of participants but measures two different variables (two scores) for each individual 48 A correlational study is used to examine the relationship between two variables but cannot determine whether it is a cause-and-effect relationship 49 A recent report concluded that children with siblings have better social skills than children who grow up as an only child This is an example of an experimental study 50 A recent report concluded that college graduates have higher life-satisfaction scores than individuals who not receive college degrees For this study, graduating versus not graduating is an example of a quasi-independent variable 51 The participants in a research study are classified as high, medium, or low in self-esteem This classification involves measurement on a nominal scale 52 A discrete variable must be measured on a nominal or an ordinal scale 53 Classifying people into two groups on the basis of gender is an example of measurement on an ordinal scale 54 Students in an introductory art class are classified as art majors and non-art majors This is an example of measurement on a nominal scale 55 To determine how much difference there is between two individuals, you must use either an interval or a ratio scale of measurement 56 If a researcher measures two individuals on a nominal scale, it is impossible to determine which individual has the larger score 57 If a researcher measures two individuals on an ordinal scale, then it is impossible to determine how much difference exists between the two people Instructor Notes - Chapter - page 12 58 For statistical purposes, there usually is not much difference between scores from an interval scale and scores from a ratio scale 59 Recording the number of students who are absent each day at a high school would be an example of measuring a discrete variable 60 A high school gym teacher records how much time each student requires to complete a onemile run This is an example of measuring a continuous variable 61 In an introductory theater class, the professor records each student’s favorite movie from the previous year The teacher is measuring a discrete variable 62 A data set is described as consisting of n = 15 scores Based on the notation being used, the data set is a sample 63 To compute (ΣX) , you first add the scores, then square the total 64 The first step in computing Σ(X + 1), is to add point to each score 2 65 For the following scores, X = (X) Scores: 1, 1, 1, 66 For the following scores, Σ(X + 1) = Scores: 1, 3, 0, 67 For the following scores, Σ(X + 1) = 81 Scores: 1, 3, 0, 68 For the following scores, Σ(X – 1) = 10 Scores: 1, 3, 69 For the following scores, ΣX = 35 Scores: 1, 3, 70 For the following scores, ΣX = 49 Scores: 1, 4, 2, Other Exam Items 71 Statistical techniques are classified into two major categories: Descriptive and Inferential Describe the general purpose of each category 72 Define the concept of "sampling error." Note: Your definition should include the concepts of sample, population, statistic, and parameter Instructor Notes - Chapter - page 13 73 (www) Describe the sequence of mathematical operations that would be used to evaluate each of the following expressions a ΣX b (ΣX) c ΣX – d Σ(X – 2) e Σ(X – 2) 74 Calculate each value requested for the following set of scores Scores: 1, 2, 0, a ΣX b ΣX c (ΣX) 75 Calculate each value requested for the following set of scores Scores: 5, 2, 4, a ΣX – b Σ(X – 2) c Σ(X – 2) 76 Calculate each value requested for the following set of scores a ΣX X Y b ΣY c ΣXΣY d ΣXY –2 –4 Answers for Multiple-Choice Questions (with section and page numbers from the text) 10 c, 1.2, p d, 1.2, p b, 1.2, p a, 1.2, p d, 1.2, p a, 1.2, p a, 1.2, p c, 1.2, p b, 1.2, p b, 1.2, p 7 7 7 11 12 13 14 15 16 17 18 19 20 c, 1.2, p a, 1.3, p 16 c, 1.3, p 16 d, 1.3, p 12 a, 1.3, p 16 c, 1.3, p 18 d, 1.3, p 16 b, 1.4, p 21 c, 1.4, p 21 b, 1.4, p 21 21 22 23 24 25 26 27 28 29 30 b, 1.4, p 23 b, 1.4, p 23 c, 1.4, p 24 d, 1.4, p 24 d, 1.4, p 24 b, 1.5, p 27 d, 1.5, p 28 c, 1.5, p 29 d, 1.5, p 28 b, 1.5, p 28 31 32 33 34 35 36 37 38 39 40 a, 1.5, p 29 d, 1.5, p 28 a, 1.5, p 29 d, 1.5, p 28 b, 1.5, p 29 d, 1.5, p 28 a, 1.5, p 28 b, 1.5, p 29 b, 1.5, p 28 c, 1.5, p 28 Answers for True/False Questions (with section and page numbers from the text) 41 F, 1.2, p 42 T, 1.2, p 43 F, 1.2, p 51 F, 1.4, p 23 52 F, 1.4, p 21 53 F, 1.4, p 23 61 T, 1.4, p 21 62 T, 1.5, p 27 63 T, 1.5, p 28 Instructor Notes - Chapter - page 14 44 45 46 47 48 49 50 F, 1.2, p T, 1.3, p 14 F, 1.3, p 13 T, 1.3, p 13 T, 1,3, p 13 F, 1.3, p 16 T, 1.3, p 18 54 55 56 57 58 59 60 T, 1.4, p 23 T, 1.4, p 24 T, 1.4, p 23 T, 1.4, p 24 T, 1.4, p 25 T, 1.4, p 21 T, 1.4, p 21 64 65 66 67 68 69 70 T, 1.5, p 28 F, 1.5, p 28 T, 1.5, p 28 F, 1.5, p 29 F, 1.5, p 28 T, 1.5, p 28 F, 1.5, p 28 Answers for Other Exam Items 71 The purpose of descriptive statistics is to simplify the organization and presentation of data The purpose of inferential statistics is to use the limited data from a sample as the basis for making general conclusions about the population 72 A parameter is a value that is obtained from a population of scores and is used to describe the population A statistic is a value obtained from a sample and used to describe the sample Typically it is impossible to obtain measurements for an entire population, so researchers must rely on information from samples; that is, researchers use statistics to obtain information about unknown parameters However, samples provide only limited information about their populations Thus, sample statistics are usually not identical to their corresponding population parameters The error or discrepancy between a statistic and the corresponding parameter is called sampling error To compute ΣX , you first square each score, then sum the squared values To compute (ΣX) , you first sum the scores, then square the sum To compute ΣX  2, you first sum the scores, then subtract from the sum To compute Σ(X – 2) you first subtract from each score, then sum the resulting values e To compute Σ(X – 2) , you first subtract from each score, then square the resulting values, then sum the squared numbers 73 a b c d 74 a b 21 c (7) = 49 75 a 11 b c 13 76 a b c d 0 Instructor Notes - Chapter - page 15 ... correct There is only one correct answer because there is only one correct sequence for performing the calculations Have the class identify the step by step sequence of operations specified by the. .. then the new stuff is just one small step forward On the other hand, if you not know the old material, then the new stuff is totally incomprehensible (For example, try reading Chapter 10 on the. .. Add the scores c Add the squared scores d Square the sum of the scores 27 What is the final step to be performed in the following mathematical expression? (ΣX) ? a Square each score b Add the