Chapter 2 Methods Flashcards Preview

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Flashcards in Chapter 2 Methods Deck (61)
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31

When a graph is negatively skewed, the mean, median, and mode are shifted...

Right.

32

Range

The value of the largest measurement in a frequency distribution minus the value of the smallest frequency.

33

Standard Deviation

A statistic that describes the average difference between the measurements in a frequency distribution and the mean of that distribution.

34

Scientific research aims to establish...

Causal relationships between properties.

35

Variable

A property whose value can vary across individuals or over time.

36

Correlation

Two variables are said to be correlated when variations in the value of one variable are synchronized with variation in the value of the other.

37

Positive Correlation

More-more or less-less.

38

Negative Correlation

More-less or less-more.

39

Correlation Coefficient

Measure of the direction and strength of a correlation.

40

Natural Correlation

A correlation observed in the world around us.

41

Third-Variable Correlation

The fact that two variables are correlated only because each is causally related to a third variable.

42

Matched Samples

A technique whereby the participants in two groups are identical in terms of a third variable.

43

Matched Pairs

A technique whereby each participant is identical to one other participant in terms of a third variable.

44

Third Variable Problem

The fact that a causal relationship between two variables cannot be infererred from the naturally occuring correlation between them because of the ever-present possibility of third-variable correlation.

45

Experiment

A technique for establishing the causal relationship between variables.

46

Experiments can eliminate differences by ___ and ___.

Manipulation and random assignment.

47

Manipulation

Creation of an artificial pattern of variation in a variable on irder to determine its causal powers.

48

Independent Variable

The variable that is manipulated in an experiment.

49

Experimental Group

The group of people who are treated in a particular way, as compated to the control group, in an experiment.

50

Control Group

The group of people who are not treated in the particular way that the experimental group is treated in an experiment.

51

Dependent Variable

The variable that is measured in a study.

52

Self-Selection

A problem that occus when anything about a person determines whether he or she will be included in the experimental or control group.

53

Random Assignment

A procedure that uses a random event to assign people to the experimental or control group.

54

Internal Validity

The characteristic of an experiment that establishes the causal relationship between variables.

55

External Validity

A property of an experiment in which the variables have been operationally defined in a normal, typical, or realistic way.

56

Population

The complete collection of participants who might possibly be measured.

57

Sample

The partial collection of people drawn from a population.

58

Case Method.

A method of gathering scientific knowledge by studying a single individual.

59

Random Sampling

A technique for chooseing participants that ensures that every member of a population has an equal chance of being included in the sample.

60

Informed Consent

A written agreement to participate in a study made by an adult who has been informed of all risks that participation may entail.