PSY 231: Introduction to Industrial and Organizational

PsychologyPsychometrics, Basic Psychometrics, Basic Statistics, & Ethics of Statistics, & Ethics of

ResearchResearch

Some important terms…Some important terms…

MeasurementMeasurement = assignment of = assignment of numbers to objects or events such numbers to objects or events such as individual attributes.as individual attributes.

AttributeAttribute = any characteristic of = any characteristic of an individual that can be measured an individual that can be measured and can vary from person to and can vary from person to personperson

Time 1 Time 2

Test-Retest Reliability

Parallel Forms Reliability

Form A Form B Form C

≈

≈ ≈

Internal Consistency Reliability

Item 1 ≈ ≈

Item 2

Item 3

VALIDITY

Construct Validity

Convergent Validity

Divergent Validity

Content Validity

CriterionValidity

PredictiveValidity

ConvergentValidity

Construct Validity

TrustworthinessHonesty Integrity

Food Preference

PhysicalAbility

Convergent Validity

Divergent Validity

Trustworthiness

Content ValidityContent Validity

HonestyTest of Honesty

Contamination

Relevance

Deficiency

Criterion ValidityCriterion Validity

Time 1 Pre-employment Test

Time 2: Performance Rating of the employee on-the-Job

Time 1: Compare test score and appraisal ratings of

current employees

Predictive Validity

Concurrent Validity

Current Employee

Appraisal Ratings

Job Applicant

Analyzing test data – Looking at the Distribution of Test Scores

MEAN (also median & mode in this example)

Standard Deviation

Range

Stats Representing Mean Differences

T-testsT-tests

ANOVA testANOVA test

Jo

b P

erf

orm

an

ce

Mechanical Comprehension

Jo

b P

erf

orm

an

ce

Mechanical Comprehension

Jo

b P

erf

orm

an

ce

Mechanical Comprehension

r = .00

r = .70 r = -.70

Stat Representing Relationships Between Variables: Correlation

Regression

Job Performa

nce

Test

(e.g., Math Skills)

r2

r = .60r2 = .36

Meta-AnalysisMeta-Analysis

Study 1 results

Study 2 results

Study 3 results

Study 4 results

+ + + …

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