The correlation between self-esteem and shyness is –.50. Interpret this correlation.
A moderate negative correlation. As self-esteem increases, shyness decreases, and vice versa.
Which is larger—a correlation of +.45 or a correlation of –.60? Explain.
–.60 is stronger because correlation strength depends on absolute value. (.60 > .45)
Tell whether each relationship reflects a positive or negative correlation.
Stress and number of colds → Positive
Sun tanning and skin damage → Positive
Happiness and suicidal thoughts → Negative
Blood pressure and hostility → Positive
Number of maze runs and time to complete maze → Negative
Why do researchers examine scatter plots in correlational research?
To visualize the relationship, direction, strength, patterns, and detect outliers.
Why calculate the coefficient of determination?
To determine how much variance in one variable is explained by another.
What does a coefficient of determination of .40 indicate?
40% of the variance is explained by the relationship.
What is a restricted range and what effect does it have?
Limited variation in data that reduces the correlation strength.
Why can’t we infer causality from correlation?
Because of directionality problems and third variables.
What is the bidirectionality problem?
When two correlated variables could cause each other.
When do researchers use regression analysis?
To predict one variable from another.
What is multiple regression analysis?
Using multiple predictor variables to predict one outcome variable.
What are constructs and operational definitions and how are they related?
Construct → abstract concept (e.g., anxiety).
Operational definition → how the construct is measured.
What is reliability and validity?
Reliability → consistency of a measure.
Validity → accuracy (measuring what it should measure).
Distinguish between the three types of reliability.
Test–retest reliability → consistency over time
Inter-rater reliability → agreement between observers
Internal consistency → items measure same construct
What is measurement error and how can it be reduced?
Difference between true value and measured value.
Reduced by:
clear procedures
reliable tools
observer training
How are measurement error and reliability related?
More error = lower reliability
Less error = higher reliability
Distinguish between face, content, and construct validity.
Face validity → appears to measure the construct
Content validity → covers all aspects of construct
Construct validity → accurately measures theoretical concept
What is a variable and types of variables?
Variable → anything that can vary.
Quantitative → numerical
Qualitative → categorical
Discrete → countable
Continuous → any value within range
Independent vs dependent variables
Independent variable (IV) → manipulated variable
Dependent variable (DV) → measured outcome
Four levels (scales) of measurement
Nominal → categories (no order)
Ordinal → ranked order
Interval → equal intervals, no true zero
Ratio → equal intervals + true zero
Distinguish between naturalistic, participant, and contrived observation.
Naturalistic → observe behavior in natural setting
Participant → researcher joins group
Contrived → behavior observed in controlled setting
What is reactivity and how can it be avoided?
Reactivity → people change behavior when observed.
Avoid by:
unobtrusive observation
hidden recording
participant habituation
Four techniques for observing behavioral data
Narrative records → detailed descriptions
Event sampling → record each behavior occurrence
Time sampling → observe at time intervals
Rating scales → rate behavior intensity
Types of temporal measures
Frequency → how often behavior occurs
Duration → how long behavior lasts
Latency → time between stimulus and response
