Research Methods Flashcards
Hypothesis
Prediction of how two or more factors are likely to be related.
Replication
Repetition of the methods used in a previous experiment to see whether the same methods will yield the same results.
Population
All of the individuals in the group to which the study applies.
Sample
The subgroup of the population that participates in the study.
Random selection
Choosing of members of a population so that every individual has an equal chance of being chosen to participate in a study.
Control Group
The comparison group; the subgroup of the sample that is similar to the experimental group in every way except for the presence of the independent variable.
Quasi-experiment
Measurement of a DV when random assignment to groups is not possible.
Random Assignment
Division of the sample into groups so that every individual has an equal chance of being put in any group or condition.
Confounding Variables
Factors that cause differences between the experimental group and the control group other than the independent variable.
Operational Definition
A description of the specific procedure used to determine the presence of a variable.
Experimenter Bias
A phenomenon that occurs when a researcher’s expectations/preferences about the outcome of a study influence the results obtained.
Demand Characteristics
Clues participants discover about the purpose of the study that suggest how they should respond.
Single-Blind Procedure
Research design in which participants don’t know whether they are in the experimental or control group.
Double-Blind Procedure
Research design in which neither the experimenter nor the participants know who is in the experimental or control group.
Placebo
A physical or psychological treatment given to the control group the resembles the treatment given to the experimental group, but contains no active ingredient.
Placebo Effect
A response to the belief that the IV will have an effect, rather than the actual effect of the IV, which can be a confounding variable.
Reliability
Consistency or repeatability of results.
Validity
The extent to which an instrument measures or predicts what it is supposed to measure or predict.
Theories
Organized sets of concepts that explain phenomena.
Statistics
A field that involves the analysis of numerical data about representative samples of populations.
Descriptive Statics
Numbers that summarize a set of research data obtained from a sample.
Frequency Distribution
An orderly arrangement of scores indicating the frequency of each score or group of scores.
Central Tendency
Average or most typical scores of a set of research data or distribution.
Mode
Most frequently occurring score in a set of research data.
Median
The middle score when a set of data is ordered by size.
Mean
The arithmetic average of a set of scores.
Variability
The spread or dispersion of a set of research data or distribution.
Range
The difference between the largest score and the smallest score.
Standard Deviation
Measures the average difference between each score and the mean of the data set.
Normal Distribution
Bell-shaped curve that represents data about how lots of human characteristics are dispersed in the population.
Percentile Score
The percentage of scores at or below a particular score (from 1 to 99).
Correlation Coefficient
A statistical measure of the degree of relatedness or association between two sets of data that ranges from -1 to +1.
Inferential Statistics
Statistics that are used to interpret data and draw conclusions.
Statistical Significance
The condition that exists when the probability that the observed findings are due to chance is less than 1 in 20 according to some psychologists, or less than 1 in 100 according to those with more stringent standards.
Ethical Guidelines
Suggested rules for acting responsibly and morally when conducting research or in clinical practice.
