Psych220 - Chapter 1

Front 1

Statistics

Back 1

the term "statistics" refers to a set of mathematical procedures for organizing, summarizing, and interpreting information

Front 2

Population

Back 2

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

Front 3

Sample

Back 3

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

Front 4

Variable

Back 4

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

Front 5

Data (plural)

Back 5

measurements or observations

Front 6

Data set

Back 6

a collection of measurements or observations

Front 7

Datum (singular)

Back 7

a single measurement or observation, otherwise known as a score or raw score

Front 8

Parameter

Back 8

a value, usually numerical, that describes a population, usually derived from measurements of the individuals in the population

Front 9

Statistic (a)

Back 9

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

Front 10

Descriptive statistics

Back 10

statistical procedures used to summarize, organize and simplify data

Front 11

Inferential statistics

Back 11

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

Front 12

Sampling error

Back 12

discrepancy or amount of error between a sample statistics and the corresponding population parameter

Front 13

Correlational method

Back 13

in the correlational method, two different variables are observed to determine whether there is a relationship between them

Front 14

Experimental method

Back 14

in the experimental method, 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 the other variables to prevent them from influencing the results

Front 15

Independent variable

Back 15

the variable that is manipulated by the researcher

Front 16

Dependent variable

Back 16

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

Front 17

pre-post studies

Back 17

a type of study which measures the same conditions at different points in time

Front 18

quasi-independent variable

Back 18

in a nonexperimental study, the "independent variable" that is used to create the different groups of scores is often called the "quasi independent variable"

Front 19

Constructs

Back 19

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

Front 20

Discrete variable

Back 20

consists of separate, indivisible categories, such as numbers

Front 21

Continuous variable

Back 21

a variable that has an infinite number of possible values that fall between any two observed values. is divisible into an infinite number of fractional parts.

Front 22

Real limits

Back 22

boundaries of intervals for scores that are represented on a continuous number line. the real limit separating two adjacent scores is located exactly halfway between the scores.

Front 23

Nominal scale

Back 23

consists of a set of categories that have different names. measurements on a nominal scale label and categorize observations, but do not make any quantitative distinctions between observations

Front 24

Ordinal scale

Back 24

consists of a set of categories that are organized in an ordered sequence. measurements on an ordinal scale rank observations in terms of size or magnitude

Front 25

Interval scale

Back 25

consists of ordered categories that are all intervals of exactly the same size. equal differences between numbers on a scale reflect equal differences in magnitude, but the zero point on an interval scale is arbitrary and does not indicate a zero amount of the variable being measured

Front 26

Ratio scale

Back 26

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

Front 27

Real limits

Back 27

The boundaries separating the intervals that define the scores for a continuous variable