Chapter 2: Methods

People have the tendency upon hearing about research findings (and many other things) to think that they knew it all along; this tendency is called

explores questions that are of interest to psychologists but are not intended to have immediate, real-world applications.

expresses a relationship between two variables.

are things that can vary among the participants in the research.

aims to explain some phenomenon and allows researchers to generate testable hypotheses with the hope of collecting data that support the theory.

When you operationalize a variable, you explain how you will measure it.

when it measures what the researcher set out to measure; it is accurate.

when it can be replicated; it is consistent.

The individuals on which the research will be conducted are called

the process by which participants are selected is called

(the group of participants)

is that every member of the population has an equal chance of being selected.

is a process that allows a researcher to ensure that the sample represents the population on some criteria.

are conducted in a lab, a highly controlled environment

are conducted out in the world.

allows the researcher to manipulate the independent variable and control for confounding variables.

is the process by which participants are put into a group, experimental or control.

means that each participant has an equal chance of being placed into any group.

The benefit of random assignment is that it limits the effect of

If one wanted to ensure that the experimental and control groups were equivalent on some criterion (e.g., sex, IQ scores, age), one could use

can also affect an experiment.

is a special kind of situation-relevant confounding variable.

Experimenter bias can be eliminated by using a

occurs when only the participants do not know to which group they have been assigned; this strategy minimizes the effect of demand characteristics as well as certain kinds of response or participant bias.

One kind of response bias, the tendency to try to give answers that reflect well upon them, is called

Merely selecting a group of people on whom to experiment has been determined to affect the performance of that group, regardless of what is done to those individuals.

This technique allows researchers to separate the physiological effects of the drug from the psychological effects of people thinking they took a drug

Sometimes using participants as their own control group is possible, a procedure known as

expresses a relationship between two variables without ascribing cause.

between two things means that the presence of one thing predicts the presence of the other.

means that the presence of one thing predicts the absence of the other.

An even more popular research design is the

The goal of naturalistic observation is to get a realistic and rich picture of the participants’ behavior.

is used to get a full, detailed picture of one participant or a small group of participants.

simply describe a set of data.

Frequency distributions can be easily turned into line graphs called

with at least one group of statistical measures called measures of

The mean is the most commonly used measure of central tendency, but its accuracy can be distorted by

When a distribution includes an extreme score (or group of scores) that is very high, as in the car example above, the distribution is said to be

When the skew is caused by a particularly low score (or group of scores), the distribution is

are other types of descriptive statistical measures.

measure the distance of a score from the mean in units of standard deviation.

indicate the distance of a score from 0.

measures the relationship between two variables.

The strength of a correlation can be computed by a statistic called the

A correlation may be graphed using a

is the line drawn through the scatter plot that minimizes the distance of all the points from the line.

is to determine whether or not findings can be applied to the larger population from which the sample was selected.

The extent to which the sample differs from the population is known as

Any type of academic research must first propose the study to the ethics board or Institutional Review Board (IRB) at the institution.

Participation should be voluntary

Participants must know that they are involved in research and give their consent.

Participants’ privacy must be protected.

Participants cannot be placed at significant mental or physical risk.

After the study, participants should be told the purpose of the study and provided with ways to contact the researchers about the results.