Research Methods Mid Term

Abstract

A summary of a research study.

Aim

The researcher’s area of interest – what they are looking at (e.g. to investigate helping behavior).

Alternative Hypothesis

The idea that there is a relationship in the population and that the relationship in the sample reflects this relationship in the population.

Analysis of Variance (ANOVA)

Most common null hypothesis test when there are more than two groups or condition means to be compared.

Applied Research

Research conducted primarily to address some practical problem.

Bar graph

A graph that shows the data in the form of categories (e.g. behaviors observed) that the researcher wishes to compare.

Baseline

The level of responding before any treatment is introduced and therefore acts as a kind of control condition.

Behavioral categories

Key behaviors or, collections of behavior, that the researcher conducting the observation will pay attention to and record

Between-subjects Experiment

An experiment in which each participant is only tested in one condition.

Between-subjects Factorial Design

All of the independent variables are manipulated between subjects.

Bystander effect

The more people who are present at an emergency situation, the less likely it is that any one of them will help.

Carryover Effect

An effect of being tested in one condition on participants’ behavior in later conditions.

Case study

In-depth investigation of a single person, group or event, where data are gathered from a variety of sources and by using several different methods (e.g. observations & interviews).

Cronbach’s alpha

α (or coefficient alpha) measures reliability, or internal consistency. In general, a score of more than 0.7 is usually okay

Closed questions

Questions where there are fixed choices of responses e.g. yes/no. They generate quantitative data

Co-variables

The variables investigated in a correlation

Concurrent validity

Comparing a new test with another test of the same thing to see if they produce similar results. If they do then the new test has concurrent validity

Convenience sample

A sampling technique where participants are chosen because they are easily available

Cluster Sampling

A method of probability sampling in which larger clusters of individuals are randomly sampled and then individuals within each cluster are randomly sampled.

Coding

A judgment on part of the observers by clearly defining a set of target behaviours.

Cohen’s κ

A statistic, analogous to Cronbach’s α, which assess interrater reliability.

Cohen’s d

The most widely used measure of effect size for differences between group or condition means; the difference between the two means divided by the standard deviation.

Concurrent Validity

When the criterion is measured at the same time as the construct.

Confidence interval

A range of values that is computed in such a way that some percentage of the time, the population parameter will lie within that range.

Confirmation Bias

The focus on cases that confirm beliefs and dismissal of cases that disprove them.

Confidentiality

Unless agreed beforehand, participants have the right to expect that all data collected during a research study will remain confidential and anonymous.

Confounding variable

An extraneous variable that varies systematically with the IV so we cannot be sure of the true source of the change to the DV

Constructs

Variables that are not straightforward or simple to measure such as intelligence.

Construct Validity

The quality of the experiment’s manipulations.

Content analysis

Technique used to analyze qualitative data which involves coding the written data into categories – converting qualitative data into quantitative data.

Control

Method of holding extraneous variables at a constant.

Control Condition

A condition in a study that the other condition is compared to. This group does not receive the treatment or intervention that the other conditions do.

Control group

A group that is treated normally and gives us a measure of how people behave when they are not exposed to the experimental treatment (e.g. allowed to sleep normally).

Controlled observation

An observation study where the researchers control some variables - often takes place in laboratory setting

convergent validity

When new measures positively correlate with existing measures of the same constructs.

Correlational analysis

A mathematical technique where the researcher looks to see whether scores for two covariables are related

Counterbalancing

A way of trying to control for order effects in a repeated measures design, e.g. half the participants do condition A followed by B and the other half do B followed by A

Covert observation

Also known as an undisclosed observation as the participants do not know their behavior is being observed

Criterion Validity

The extent to which people’s scores on a measure are correlated with other variables that one would expect them to be correlated with.

Critical value

The value that a test statistic must reach in order for the hypothesis to be accepted.

Cronbach’s α

A statistic in which α is the mean of all possible split-half correlations for a set of items.

Debriefing

After completing the research, the true aim is revealed to the participant. Aim of debriefing = to return the person to the state s/he was in before they took part.

Deception

Involves misleading participants about the purpose of study.

Demand characteristics

Occur when participants try to make sense of the research situation they are in and try to guess the purpose of the research or try to present themselves in a good way.

Dependent-samples T Test

Statistical test used to compare two means for the same sample tested at two different times or under two different conditions.

Dependent variable

The variable that is measured to tell you the outcome.

Descriptive statistics

Analysis of data that helps describe, show or summarize data in a meaningful way

Discriminant Validity

The extent to which scores on a measure are not correlated with measures of variables that are conceptually distinct.

Directional hypothesis .

A one-tailed hypothesis that states the direction of the difference or relationship (e.g. boys are more helpful than girls)

Dispersion measure

A dispersion measure shows how a set of data is spread out, examples are the range and the standard deviation

Double blind control

Participants are not told the true purpose of the research and the experimenter is also blind to at least some aspects of the research design.

Effect Size

The strength of a statistical relationship.

Empirical Questions

The second fundamental feature of science; questions about the way the world actually is and can be answered through systematic empiricism.

Ecological validity

The extent to which the findings of a research study are able to be generalized to real-life settings

Ethical guidelines

These are provided by the BPS - they are the ‘rules’ by which all psychologists should operate, including those carrying out research.

Ethical issues

There are 3 main ethical issues that occur in psychological research – deception, lack of informed consent and lack of protection of participants.

Evaluation apprehension

Participants’ behavior is distorted as they fear being judged by observers

Event sampling

A target behavior is identified and the observer records it every time it occurs

Experimenter Expectancy Effect

A source of variation in which the experimenter’s expectations about how participants “should” behave in the experiment.

Experimental group

The group that received the experimental treatment (e.g. sleep deprivation)

External validity

Whether it is possible to generalize the results beyond the experimental setting.

Extraneous variable

Variables that if not controlled may affect the DV and provide a false impression than an IV has produced changes when it hasn’t.

Face validity

Simple way of assessing whether a test measures what it claims to measure which is concerned with face value – e.g. does an IQ test look like it tests intelligence.

Factor

In a factorial design, each level of one independent variable.

Factor Analysis

A statistical technique that organizes the variables into a smaller number of clusters, such that they are strongly correlated within each cluster but weakly correlated between clusters.

Factorial ANOVA

A null hypothesis test that is used when more than one independent variable is included in a factorial design.

Factorial Design

An approach to including multiple independent variables in an experiment where each level of one independent variable is combined with each level of the others to produce all possible combinations.

Fatigue Effect

Participants perform a task worse in later conditions because they become tired or bored.

Field experiment

An experiment that takes place in a natural setting where the experimenter manipulates the IV and measures the DV

Focus Groups

Small groups of people who participate together in interviews focused on a particular topic or issue.

Grounded Theory

Researchers start with the data and develop a theory or interpretation that is “grounded in” the data.

Histogram

A graph that is used for continuous data (e.g. test scores). There should be no space between the bars, because the data is continuous.

Hypothesis

This is a formal statement or prediction of what the researcher expects to find. It needs to be testable.

Independent groups design

An experimental design where each participant only takes part in one condition of the IV

Independent variable

The variable that the experimenter manipulates (changes)

Independent-samples T Test

Statistical test used to compare the means of two separate samples.

Inferential statistics

Inferential statistics are ways of analyzing data using statistical tests that allow the researcher to make conclusions about whether a hypothesis was supported by the results.

Informed consent

Psychologists should ensure that all participants are helped to understand fully all aspects of the research before they agree (give consent) to take part

Inter-observer reliability (interrater reliability)

The extent to which two or more observers are observing and recording behavior in the same way

Internal validity

In relation to experiments, whether the results were due to the manipulation of the IV rather than other factors such as extraneous variables or demand characteristics.

Interval level data

Data measured in fixed units with equal distance between points on the scale

Interrupted Time-series Design

A set of measurements taken at intervals over a period of time that are interrupted by a treatment.

Interval Level

Level of measurement in which scores represent the precise magnitude of the difference between individuals, but a score of 0 does not represent an absence of the characteristic.

Investigator effects

These result from the effects of a researcher’s behavior and characteristics on an investigation.

Laboratory experiment

An experiment that takes place in a controlled environment where the experimenter manipulates the IV and measures the DV

Latency

The time it takes for the dependent variable to begin changing after a change in conditions.

Line Graphs

A graph used to present correlations between quantitative variables when the independent variable has, or is organized into, a relatively small number of distinct levels.

Main Effect

In factorial design, the statistical relationship between one independent variable and a dependent variable--averaging across the levels of the other independent variable.

Manipulate

To change an independent variable’s level systematically so that different groups of participants are exposed to different levels of that variable, or the same group of participants is exposed to different levels at different times.

Matched pairs design

An experimental design where pairs of participants are matched on important characteristics and one member allocated to each condition of the IV

Maturation

An alternative explanation that refers to how the participants might have changed between the pretest and posttest in ways that they were going to anyway because they are growing and learning.

Mean

Measure of central tendency calculated by adding all the scores in a set of data together and dividing by the total number of scores

Measures of central tendency

A measurement of data that indicates where the middle of the information lies e.g. mean, median or mode

Median

Measure of central tendency calculated by arranging scores in a set of data from lowest to highest and finding the middle score

Meta-analysis

A technique where rather than conducting new research with participants, the researchers examine the results of several studies that have already been conducted

Mixed-methods Research

The combination of quantitative and qualitative research.

Mode

Measure of central tendency which is the most frequently occurring score in a set of data

Multiple Dependent Variables

When researchers examine the relationship between a single independent variable and more than one dependent variable.

Multiple Regression

Measuring several independent variables, all of which are possible causes of a single dependent variable. This results in an equation that expresses the dependent variable as an additive combination of the independent variables.

Multiple-baseline Design

A baseline is established for several participants and the treatment is then introduced to each participant at a different time.