Chapter 1

Question 1

statistics (term)

Answer 1

refers to a mathematical set of procedures for organizing, summarizing, and interpreting information

Question 2

Population

Answer 2

the set of all the individuals of interest in a particular study.

Question 3

Sample

Answer 3

a set of individuals selected from a population, usually intended to represent the population in a research study.

Question 4

The relationship between a population and a sample.

Answer 4

a researcher studies a sample and then generalizes the results from the sample to the population.

Question 5

Variable

Answer 5

a characteristic or condition that changes or has different values for different individuals.

Question 6

Datum

Answer 6

(singular) is a single measurement or observation and is commonly called a score or raw score.

Question 7

Data

Answer 7

(plural) are measurements or observations.

Question 8

Parameter

Answer 8

a value, usually a numerical value, that describes a population. A parameter is usually derived from measurements of the individuals in the population.

Question 9

Statistic

Answer 9

is a value, usually a numerical value, that describes a sample. A statistic is usually derived from measurements of the individuals in the sample.

Question 10

Descriptive Statistics

Answer 10

statistical procedures used to summarize, organize, and simplify data.

Question 11

inferential statistics

Answer 11

consist of techniques that allow us to study samples and then make generalizations about the populations from which they were selected.

Question 12

sampling error

Answer 12

is the naturally occurring discrepancy, or error, that exists between a sample statistic and the corresponding population parameter.

Question 13

Sampling error example

Answer 13

Because the characteristics of each sample depend on the specific people in the sample, statistics will vary from one sample to another. For example, the five students in sample 1 have an average age of 19.8 years and the students in sample 2 have an average age of 20.4 years.

Question 14

Relationships between Variables

Answer 14

Most research, however, is intended to examine relationships between two or more variables.

Question 15

correlational method

Answer 15

two different variables are observed to determine whether there is a relationship between them.

Question 16

Chi-square tests

Answer 16

summary tables

Question 17

scatter plot

Answer 17

a graph in which each individual is represented by a point so that the horizontal position corresponds to the student’s wake-up time and the vertical position corresponds to the student’s academic performance score.

Question 18

Limitations of the Correlational Method

Answer 18

The results from a correlational study can demonstrate the existence of a relationship between two variables, but they do not provide an explanation for the relationship.We can say that changes in one variable are accompanied by changes in a second variable, but we cannot say why.

Question 19

experimental method/experimental research strategy

Answer 19

one variable is manipulated while another variable is observed and measured. To establish a cause-and-effect relationship between the two variables, an experiment attempts to control all other variables to prevent them from influencing the results.

Question 20

Manipulation

Answer 20

The researcher manipulates one variable by changing its value from one level to another

Question 21

Control

Answer 21

The researcher must exercise control over the research situation to ensure that other, extraneous variables do not influence the relationship being examined.

Question 22

When using the experimental method to correlate two or more manipulated and controlled variables, what are two general categories of variables that researchers must consider?

Answer 22

Participant variables

environmental variables

Question 23

Three basic techniques to control other variable

Answer 23

random assignment, matching, holding them constant

Question 24

*Independent Variable

Answer 24

is the variable that is manipulated by the researcher. In behavioral research, the independent variable usually consists of the two (or more) treatment conditions to which subjects are exposed. The independent variable consists of the antecedent conditions that were manipulated prior to observing the dependent variable.

Question 25

*Dependent Variable

Answer 25

the variable that is observed to assess the effect of the treatment.

Question 26

Correlational method vs Experimental method

Answer 26

In a correlational methods, both or more variables are measured. In experimental methods, one or more variable is controlled and manipulated (independent) while only one variable is observed (dependent).

Question 27

Control condition

Answer 27

An individual does not receive the experimental treatment. Instead, they either receive no treatment or they receive a neutral, placebo treatment. The purpose of a control condition is to provide a baseline comparison with the experimental condition.

Question 28

experimental condition

Answer 28

Individuals who receive the experimental treatment.

Question 29

Non-experimental study

Answer 29

A study that does not have control and experimental groups.

Question 30

nonequivalent groups

Answer 30

A research study in which the different groups of participants are formed under circumstances that do not permit the researcher to control the assignment of individuals to groups and the groups of participants are, therefore, considered nonequivalent.

Question 31

pre–post study

Answer 31

Quasi-experimental and nonexperimental designs consisting of a series of observations made over time. The goal is to evaluate the effect of an intervening treatment or event by comparing observations made before versus after the treatment.

Question 32

quasi-independent variable.

Answer 32

the “independent variable” (considered but not really) that is used to create the different groups of scores

Question 33

discrete variable

Answer 33

variables that are counted (how many marbles) A discrete variable consists of separate, indivisible categories. No values can exist between two neighboring categories.

Question 34

continuous variable

Answer 34

variables that are measured (height inches) there are an infinite number of possible values that fall between any two observed values. A continuous variable is divisible into an infinite number of fractional parts.

Question 35

Constructs

Answer 35

internal attributes or characteristics that cannot be directly observed but are useful for describing and explaining behavior.

Question 36

Nonequivalent group study

Answer 36

A research study in which the different groups of participants are formed under circumstances that do not permit the researcher to control the assignment of individuals to groups and the groups of participants are, therefore, considered nonequivalent.

Question 37

A ratio scale

Answer 37

is an interval scale with the additional feature of an absolute zero point. With a ratio scale, ratios of numbers do reflect ratios of magnitude.

Question 38

operational definition

Answer 38

identifies a measurement procedure (a set of operations) for measuring an external behavior and uses the resulting measurements as a definition and a measurement of a hypothetical construct. Note that an operational definition has two components. First, it describes a set of operations for measuring a construct. Second, it defines the construct in terms of the resulting measurements.