Shared Flashcard Set

Details

PSY 395 Final
Psychology 395 - Design & Measurement final exam study guide terms
60
Psychology
Undergraduate 4
12/11/2012

Additional Psychology Flashcards

 


 

Cards

Term
Experimental
Definition
A research procedure in which some factor is varied, all else is held constant, and some result is measured.
Term
Joint Method of Agreement and Difference
Definition
If two or more instances in which the phenomenon occurs have only one circumstance in common, while two or more instances in which it does not occur have nothing in common save the absence of that circumstance: the circumstance in which alone the two sets of instances differ, is the effect, or cause, or a necessary part of the cause, of the phenomenon.
Term
Independent Variable
Definition
The factor of interest to the researcher; it can be directly manipulated by the experimenter or participants can be selected by virtue of their possessing certain attributes.
Term
Dependent Variable
Definition
Behavior measured as the outcome of an experiment.
Term
Ceiling Effect
Definition
Occurs when scores on two or more conditions are at or near the maximum possible for the scale being used, giving the impression that no differences.
Term
Floor Effect
Definition
Occurs when scores on two or more conditions are at or near the minimum possible for the scale being used, giving the impression that no differences exist between the conditions.
Term
Control Group
Definition
A group not given a treatment that is being evaluated in a study; provides a means of comparison.
Term
Control Variable
Definition
A condition where no treatment is administered to create comparison.
Term
Intact Groups
Definition
"Pre-made", already established groups. For example, all of the students enrolled in PSY 395 FS12.
Term
Random Assignment
Definition
The most common procedure for creating equivalent groups in a between-subjects design; each individual volunteering for the study has an equal probability of being assigned to any one of the groups in the study.
Term
Block Randomization
Definition
Used to accomplish random assigned and ensure an equal number of participants in each condition; ensures that each condition of the study has a subject randomly assigned to it before any condition has a subject assigned to it again.
Term
Solomon Design
Definition

A four part designed used when it is suspected that in taking a test more than once, earlier tests have an effect on later tests

[image]

Term
Regression to the Mean
Definition
If a score on a test is extremely high or low, a second score taken will be closer to the mean score; can be a threat to the internal validity of a study if a pretest score is extreme and the posttest score changes in the direction of the mean.
Term
History
Definition
A threat to the internal validity of a study; occurs when some historical event that could affect participants happens between the beginning of a study and its end.
Term
Maturation
Definition
A threat to the internal validity of a study; occurs when participants change from the beginning to the end of the study simply as a result of maturational changes within them and not as a result of some independent variable.
Term
Reactivity
Definition
Occurs when participants' behavior is influenced by the knowledge that they are being observed and their behavior is being recorded in some fashion.
Term
Experimenter Effects
Definition
If experimenters treat subjects differently in the different groups of the experiment in ways other than those required to implement the independent variable.
Term
Experimental Research Designs
Definition
Natural Groups Design
Randomized Groups Design/Between Subjects
Matched Groups Design
Repeated Measures Design/Within Subjects
Term
Natural Groups Design
Definition
Testing intact groups.
Term
Participant/Subject Variable
Definition
Individual Differences serve as IV; Cannot “assign” subjects; Subject-variable confounds; Difficult to draw causal inferences.
Term
Matched Groups
Definition
A between subjects design that uses a manipulated independent variable and has at least two groups of participants; subjects are matched on some variable assumed to affect the outcome before being randomly assigned to the groups.
Term
Within Subjects
Definition
Any experimental design in which the same participants serve in each of the different conditions of the study; also called a "repeated-measures design".
Term
Between Subjects
Definition
Any experimental design in which different groups of participants serve in the different conditions of the study.
Term
Sequence Effect
Definition
Can occur in a within-subjects design when the experience of participating in one of the conditions of the study influences performance.
Term
Counterbalancing
Definition
For a within-subjects variable, any procedure designed to control for sequence effects.
Term
Latin Square
Definition

Form of partial counterbalancing in which each condition of the study occurs equally often in each sequential position and each condition precedes and follows each other condition exactly one time

[image]

 

Term
External Validity
Definition
The extent to which the findings of a study generalize to other populations, other settings, and other times.
Term
Relational (Correlational)
Definition
Research attempts to determine how to or more variables are related to each other.
Term
Cross Lagged Panel Correlational Procedure
Definition
If variables X and Y are measured at two different times. If X at Time 1 is correlated with Y at time 2 but Y at time 1 is not correlated with X at time 2 then X might cause Y, but Y probably does not cause X.

** Helps determine directionality, strengthen case for causality
Term
Internal Validity
Definition
The extent to which a study is free from methodological flaws, especially confounding factors.
Term
Spurious Relationships
Definition
A correlation that can be explained by a third variable.
Term
Mediator
Definition
The mechanism by which the focal independent variable affects the dependent variable of interest.
Full mediation and Partial Mediation
Term
Testing Mediation
Definition
Step 1: Estimate the association between the IV & DV
Step 2: Estimate the association between the Mediator & IV
Step 3: Estimate the association between the mediator and the DV
Step 4: The association between the IV an DV must be reduced when the Mediator is accounted for.
Term
Regression
Definition
Regression gives best fit line through data in terms of predicting Y from X
Term
Partition of Variance
Definition
Total variability = residual variability + explained variability
Term
Coefficient of Determination
Definition
For two correlated factors, the proportion of variance in one factor that can be attributed to the second factor; found by squaring Pearson's r.
Term
Restriction of Range
Definition
Limited variability in a population that leads to a diminished correlation.
Term
Multiple Regression
Definition
A multivariate analysis that includes a criterion variable and two or more predictor variables; the predictors will have different weights.
Term
Directionality Problem
Definition
In correlational research, this refers to the fact that for a correlation between variables X and Y, it is possibly that X is causing Y, but it is also possibly that Y is causing X; the correlation along provides no basis for deciding between the two alternatives
Term
Types of Independent Variables
Definition
[image]
Term
ANOVA
Definition
Short for Analysis of Variance. The most common inferential statistical tool for analyzing the results of experiments when dependent variables are measured on interval or ratio scales.
Omnibus test
Tells IF there is an effect, not where.
Term
Within Groups Variance
Definition

If σ = σA = σB = σC then the best estimate of the population variance is the average of the sample variances:

[image]

Term
Between Groups Variance
Definition

If μ = μs = μN = μA then the variability we see between the sample means of each condition is just a function of the population variance:

[image]

Term
Factorial Design
Definition
Any experimental design with more than one independent variable.
Term
Main Effect
Definition
Refers to whether or not statistically significant differences exist between the levels of an independent variable in a factorial design.
Term
Interaction
Definition
In a factorial design, occurs when the effect of one independent variable depends on the level of another independent variable
Term
Different Patterns of Interaction
Definition
Cross over, partial cross over, no cross over.
Term
No Interaction
Definition
Lines are parallel, never interact
Term
Partial Interaction
Definition
Depending on scale, lines may cross or not (ARE NOT PARALLEL - Some relationship exists)
Term
Statistical Interpretation of Effects in Factorial
Definition
If you have significant cross over interaction, where the direction of the effect of one variable depends on the other variable, the main effects aren’t really meaningful.
Term
8 Sets of Possible Effects - 2 Factor Design
Definition
1.Main effect for factor A
2.Main effect for factor B
3.Main effects for A and B only
4.Main effect for A plus an interaction
5.Main effect for B plus an interaction
6.Main effects for both A and B plus an interaction
7.An interaction only, no main effects
8.No main effects, no interaction
Term
Mixed P x E Factorial Design
Definition
A factorial design with at least one between-subjects and one within-subjects factor
Term
P X E Factorial Design
Definition
A factorial design with at least one subect factor (P= person variable) and one manipulated factor (E=environmental variable)
Term
The Sleeper Effect
Definition
When a persuasive message (e.g., political ad) that is paired with a discounting cue (e.g., paid for by lobbyists) appears to gain credibility over time.
Term
Hypothesis Testing (Steps)
Definition
1. State your hypotheses in terms of means
2. Establish your alpha level, then specify your decision criteria using t scores.
3. Calculate the t score given the null hypothesis.
4. Make a decision and draw your conclusion.
Term
Type I Error
Definition
Rejecting the null hypothesis when it is true; finding a statistically significant effect when no true effect exists.
Term
Type II Error
Definition
Failing to reject the null hypothesis when it is false; failing to find a statistically significant effect when the effect truly exists.
Term
Problems with Hypothesis Testing
Definition
Type I & II Errors, Optional Stopping, p-Hacking, Replication, p Values are Confusing, α is arbitrary
Term
Optional Stopping
Definition
When a researcher does not fix the sample size a priori, but sets out to obtain a significant p value by using the following stopping rule:
“Continue testing additional subjects until |Z| > zcrit.”
Term
p-Hacking
Definition
Researchers have a lot of freedom in the studies they run.
- Should we collect more data?
- Should we exclude some observations?
- Which conditions should be combined and which ones compared?
Supporting users have an ad free experience!