Chapter 2: Reseach Methods Flashcards
Scientific method
The process of basing one’s confidence in an idea on systematic, direct observations of the world, usually by setting up research studies to test ideas.
Theory-data cycle
The process of the scientific method, in which scientists collect data that can either confirm or disconfirm a theory.
Theory
A set of propositions explaining how and why people act, think, or feel.
Hypothesis
A specific prediction stating what will happen in a study if the theory is correct.
Data
A set of empirical observations that scientists have gathered.
Replication
When a study is conducted more than once on a new sample of participants, and obtains the same basic results.
Journal
A periodical containing peer-reviewed articles on a specific academic discipline, written for a scholarly audience.
Variable
Something of interest that varies from person to person or situation to situation.
Measured variable
A variable whose values are simply recorded.
Manipulated variable
A variable whose values the researches controls, usually by assigning different participants to different levels of that variable.
Operational definitions
Specific ways of measuring or manipulating an abstract variable in a particular study.
Descriptive research
A type of study in which researchers measure one variable at a time.
Sample
The group who participated in research, and who belong to the larger group (the population of interest) that the research is interested in understanding.
Population of interest
The full set of cases the researcher is interested in.
Random sampling
A way of choosing a sample of participants for a study in which participants are selected without bias, for example, by dialing random digits on the telephone or pulling names out a hat.
Naturalistic observation
An observational research method in which psychologists observe the behaviour of animals and people in their normal, everyday worlds and environments.
Observational research
A descriptive research method in which psychologists measure their variable of interest by observing and recording what people are doing.
Case study
An observational research method in which researchers study one or two individuals in-depth, often those who have unique condition.
Correlational research
A type of study that measures two (or more) variables in the same sample of people, and then observes the relationship between them.
Scatterplot
A figure used to represent a correlation, in which each dot usually represents a study participant, the x-axis represents one variable, and the y-axis represents the other variable.
Third -variable problem
For a given observed relationship between two variables, an additional variable that is associated with both of them, making the additional variable an alternative explanation for the observed relationship.
Experimental research
A study in which one variable is manipulated, and the other is measured. Experimental research can provide evidence that one variable causes another.
Independent variable
The manipulated variable in an experiment.
Dependent variable
The measured variable in an experiment.
Random assignment
A procedure used in experimental research in which a random method is used to decide which participants will receive each level of the independent variable.
Experimental group
In an experiment, a group or condition in which some proposed cause is present.
Control group
In an experiment, a group or condition in which some proposed cause is not present.
Placebo condition
In an experiment, a group in which people expect to receive a treatment but are exposed only to an inert version , such as a sugar pill.
Random sampling
A way of choosing a sample of participants for a study in which participants are selected without bias, for example, by dialing random digits on the telephone or pulling names out of a hat.
Validity
The appropriateness or accuracy of a conclusion or decision.
Construct validity
The specific assessment of how accurately the operationalizations used in a study capture the variables of interest.
Reliability
The degree to which a measure yields consistent results each time it is administered.
External validity
The degree to which it is reasonable to generalize from a study’s sample to its population of interest.
Internal validity
The ability of a study to rule out alternative explanations for a relationship between two variables; one of the criteria for supporting a causal claim.
Confound
An alternative explanation for a relationship between two variables; specifically, in an experiment, when two experiment groups accidentally differ on more than just the independent variable, which causes a problem for internal validity.
Descriptive statistics
Graphs of computations that describe the characteristics of a batch of scores, such as its distribution, central tendency, or variability.
Frequency distribution
A descriptive statistic that takes the form of a bar graph in which the possible scores on a variable are listed on the x-axis and the total number of people who had each score is plotted on the y-axis.
Mean
A measure of central tendency that is the arithmetic average of a group of scores.
Median
A measure of central tendency that is the middlemost score; it is obtained by lining up the scores from the smallest to the largest and identifying the middle score.
Mode
A measure of central tendency that is the most common score in a batch of scores.
Variability
The extent to which the scores in a batch differ from each other.
Standard deviation
A variability statistic that calculates how much, on average, a batch of scores varies around its mean.
Effect size
A numerical estimate of the strength of the relationship between two variables. It can take the form of a correlation coefficient or, for an experiment, the difference between two group means divided by the standard deviations of the two groups.
Inferential statistics
A set of procedures used to estimate whether a pattern of results represents a true relationship or difference in the population.
Statistical significance
A process of inference that applies rules of logic and probability to estimate whether the results obtained in a study’s sample are the same in a larger population.
Meta-analysis
A process in which researchers locate all of the studies that have tested the same variables and mathematically average them to estimate the effect size of the entire body of studies.
False positive
A statically significant finding that does not reflect a real effect.
HARKing
A questionable research practice known as “hypothesizing after the results are know,” in which researchers create an after-the-fact hypothesis about an unexpected research result, making it appear as if they predicted it all along.
p-hacking
A family of questionable data analysis techniques, such as adding participants after the results are initially analyzed, looking for outliers, or trying new analyses in order to obtain p value of just under .05, which can lead to nonreplicable results.
Open science
The practice of sharing one’s data, hypotheses, and materials freely so others can collaborate, use, and verify the results.
Preregistration
A researcher’s public statement of a study’s expected outcome before collecting any data.
Institutional Review Board (IRB)
A local panel of researchers, teachers, citizens, and others who determine whether a research study lives up to the community’s ethical standards.
Informed consent
An application of the ethical principals of autonomy, in which a researcher explains the procedures of a study, including its risks and potential benefits, to the potential participants, who then decide whether to take part.
