Unit 0 - Research Methods and Data Interpretation

Critical Thinking

Thinking that does not automatically accept arguments and conclusions. Rather, it examines assumptions, appraises the source, discerns hidden biases, and assesses conclusions.

Hindsight Bias

The tendency to believe, after learning an outcome, that one would have foreseen it.

Overconfidence

The tendency to be more confident than correct—to overestimate the accuracy of our beliefs and judgments.

Peer Reviewers

Scientific experts who evaluate a research article's theory, originality, and accuracy.

Theory

An explanation using an integrated set of principles that organizes observations and predicts behaviors or events.

Hypothesis

A testable prediction, often implied by a theory

Falsifiability

The possibility that an idea, hypothesis, or theory can e disproven by observation or experiment.

Operational Definition

A carefully worded statement of the exact procedures (operations) used in a research study. Also known as operationalization.

Replication

repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding can be reproduced.

Case Study

A non-experimental technique in which one individual or group is studied in depth in the hope of revealing universal principles.

Naturalistic Observation

A non-experimental technique of observing and recording behavior in naturally occurring situations without trying to manipulate or control the situation.

Survey

A non-experimental technique for obtaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.

Social Desirability Bias

Bias from people's responding in ways they presume a researcher expects or wishes.

Self-Report Bias

Bias when people report their behavior innacurately

Sampling Bias

a flawed sampling process that produces an unrepresentative sample

Random sample

A sample that fairly represents a population because each member has an equal chance at inclusion

Population

All those in a group being studied, from which random samples may be drawn.

Correlation

A measure of the extent to which two factors vary together, and thus of how well either factor predicts the other.

Correlation Coefficient

A statistical index of the relationship between two variables (from -1.00 to 1.00)

Variable

Anything that can vary and is feasible and ethical to measure.

Illusory Correlation

Perceiving a relationship where none exists, or perceiving a stronger-than-actual relationship.

Regression toward the mean

The tendency for extreme or unusual scores or events to fall back towards the average.

Experiment

A research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process.

Experimental Group

In an experiment, the group that is exposed to the treatment - that is, to one version of the independent variable.

Control Group

In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.

Random Assignment

assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups

Single Blind Procedure

Ann experimental procedure in which the research participants are ignorant about whether they have received the treatment or placebo.

double blind procedure

an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or a placebo. Commonly used in drug-evaluation studies.

Placebo Effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent.

Independent Variable

In an experiment, the factor that is manipulated; the variable whose effect is being studied

dependent variable

In an experiment, the outcome that is measured; the variable that may change when the independent variable is manipulated

Confounding Variable

In an experiment, a factor other than the factor being studied that influences a study's results.

Experimenter Bias

Bias caused when researchers may unintentionally influence results to confirm their own beliefs.

Validity

The extent to which a test or experiment measures or predicts what it is supposed to do.

Quantitative Research

A research method that relies on quantifiable, numerical data.

Qualitative Research

A research method that relies on in-depth, narrative data that are not translated into numbers.

Informed Consent

Giving potential participants enough information about a study to enable them to choose whether they wish to participate.

Debriefing

the postexperimental explanation of a study, including its purpose and any deceptions, to its participants

descriptive statistics

Numerical data used to measure and describe the characteristics of groups; includes measures of central tendency and measures of variation

histogram

a bar graph depicting a frequency distribution

mode

the most frequently occurring score(s) in a distribution.

mean

the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores

median

the middle score in a distribution; half the scores are above it and half are below it.

percentile rank

the percentage of scores that are lower than a given score

skewed distribution

a representation of scores that lack symmetry around their average value

range

the difference between the highest and lowest scores in a distribution.

standard deviation

A compared measure of ow much scores vary around the mean score

normal curve

the symmetrical bell-shaped curve that describes the distribution of many physical and psychological attributes. Most scores fall near the average, and fewer and fewer scores lie near the extremes.

inferential statistics

numerical data that allow one to generalize - to infer from sample data the probability of something being true of a population

meta-analysis

a statistical procedure for analyzing the results of multiple studies to reach an overall conclusion

statistical significance

a statistical statement of how likely it is that an obtained result occurred by chance.

effect size

the strength of the relationship between two or more variables. The larger it is, the more one variable can be explained by the other.

Cultural Norms

Behavior patterns that are typical of specific groups

Confirmation Bias

A tendency to search for information that supports our preconceptions and to ignore or distort contradictory evidence

Random Assignment

Assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups

Institutional Review

Process of examining studies for ethical concerns by a committee of peers

Informed Assent

Participant's agreement to participate in the absence of full understanding.

Commonly applies to individuals who are under age or otherwise incapable of consent.

Confidentiality

The act of holding information in confidence, not to be released to unauthorized individuals

Deception

An act that misleads participants about the true purpose of a study or the events that will actually transpire

Research Confidentiality

The requirement for participants data to be secured/coded for anonymity.

Variation

A change or slight difference in condition, amount, or level.

Skewness

A measure of the degree to which a distribution is asymmetrical

Scatterplot

A graphed cluster of dots, each of which represents the values of two variables. Typically used in representations of correlation.

Bimodal Distribution

A frequency distribution that features two different values that are heavily populated with cases.