Research CHPT 5

self-report measure

a method of measuring a variable in which people answer questions about themselves in a questionnaire or interview

conceptual definition

a researchers definition of a variable at the theoretical level

• applies to the real world

observational measure

a method of measuring a variable by recording observable behaviors or physical traces of behaviors

physiological measure

a method of measuring a variable recording biological data

categorical variables

a variable whose levels are categories (nominal variables)

quantitative variables

a variable whose values can be recorded as meaningful numbers (continous)

ordinal scale

levels represent ranked order, distances between levels are not equal

• finishers in a race

interval scale

has NO true zero, numerals represent equal intervals between levels

• temperature

ratio scale

Has a true zero, numerals represent equal intervals between levels

• correct answers on a test

reliability

the consistency of the results of a measure

validity

The appropriateness of a conclusion or decision

test-retest reliability

the consistency in results every time a measure is used

interrater reliability

the degree to which 2 or more observers give consistent ratings of a set of targets

internal reliability

in a measure with several items, the consistency in a pattern of answers, no matter the phrasing of a question

correlation coefficient

a single number ( r ), from -1.0 to 1.0, indicating strength and direction of an association between two variables

slope direction

/ = positive \ = negative — = no correlation

strength

a description of an association indicating how closely the data points in a scatterplot cluster along a line of best fit

average inter-item correlation (AIC)

measure of internal reliability for a set of items

• mean of all positive correlations

cronbach’s alpha

correlation based statistic that measures a scales internal reliability

face validity

extent to which a measure is subjectively considered a plausible operalization of the conceptual variable

content validity

extent to which a measure captures all parts of a defined construct

criterion validity

empirical form of measurement validity, establishes the extent to which a measure is associated with a behavioral outcome with which it should be associated

known groups paradigm

a method for establishing criterion validity, in which a researcher tests 2+ groups that are known to differ on the variable of interest, to ensure they score differently on a measure of that variable

convergent validity

empirical test of the extent to which a self-report measure correlates with other measures of a theoretically similar construct

discriminant validity

self-report measure DOESN’T correlate strongly with measures of theoretically dissimilar constructs