Research Methods
correlation coefficient
A measure of the degree of relationship between two sets of scores. It can vary between 1.00 and +1.00.
carryover effects
One concern with single-case designs; participants carry something with them from one condition to another.
nominal scale
A scale in which objects or individuals are assigned to categories that have no numerical properties. -Ranking by gender or political affiliation
ordinal scale
A scale in which objects or individuals are categorized and the categories form a rank order along a continuum. -Age range for siblings
interval scale
A scale in which the units of measurement (intervals) between the numbers on the scale are all equal in size. -Fahrenheit Scale
maturation effect
(Threats to Internal Validity) A threat to internal validity in which participants' naturally occurring changes could be responsible for the observed results. -like physical maturing or deterioration
variable
An event or behavior that has at least two values.
Weak, Moderate, and Strong Correlation Coefficients
.70-1.00 .30-.69 .00-.29 -reliability depends on .80 or higher
between-participants design
An experiment in which different participants are assigned to each group.
college sophomore problem
(Threat to External Validity) An external validity problem that results from using mainly college sophomores as participants in research studies. -most conclusions are based on studies of young people with a late adolescent mentality who are still developing their own identities and attitudes
pretest/posttest control group design
An experimental design in which the dependent variable is measured both before and after manipulation of the independent variable.
posttest-only control group design:
An experimental design in which the dependent variable is measured after the manipulation of the independent variable.
history effect
(Threats to Internal Validity) A threat to internal validity in which an outside event that is not a part of the manipulation of the experiment could be responsible for the results. -checking dependent variable measure on college kids' stress, but doing at the time of midterms or finals
instrumentation effect
(Threats to Internal Validity) A threat to internal validity in which changes in the dependent variable may be due to changes in the measuring device. -Like a researcher who makes the measurements becoming more fatigued or being altered through the experiment
mortality (attrition)
(Threats to Internal Validity) A threat to internal validity in which differential dropout rates may be observed in the experimental and control groups, leading to inequality between the groups.
diffusion of treatment
(Threats to Internal Validity) A threat to internal validity in which observed changes in the behaviors or responses of participants may be due to information received from other participants in the study.
testing effect
(Threats to Internal Validity) A threat to internal validity in which repeated testing leads to better or worse scores. -As an example, if participants took the same math test before and after participating in a special math course, the improvement observed in scores might be due to participants familiarity with and practice on the test items. This type of testing confound is sometimes referred to as a practice effect. -Testing can also result in the opposite effect, a fatigue effect (sometimes referred to as a negative practice effect). Repeated testing fatigues the participants, and their performance declines as a result.
Nonequivalent control group
(Threats to Internal Validity) Problems in participant selection or assignment may lead to important differences between the participants assigned to the experimental and control groups
At Risk in a study
-If privacy is compromised -physical or emotional harm is called into question
Negative Relationship
-on a scatter plot. Graphs negative correlation -Example: Mountain elevation and temperature
single-blind experiment
An experimental procedure in which either the participants or the experimenter are blind to the manipulation being made.
participant (subject) variable:
A characteristic of the participants that cannot be changed. -such as their age
pseudoscience
A claim that appears to be scientific but that actually violates the criteria of science.
Institutional Review Board (IRB):
A committee charged with evaluating research projects in which human participants are used.
partial correlation
A correlational technique that involves measuring three variables and then statistically removing the effect of the third variable from the correlation of the remaining two.
operational definition
A definition of a variable in terms of the operations (activities) a researcher uses to measure or manipulate it. -Specifying hunger in terms of the number of hours without food is an operational definition; defining hunger as that gnawing feeling is not. Researchers must operationally define all variables, both dependent and independant
archival method
A descriptive research method that involves describing data that existed before the time of the study. -Ex: Testing the number of babies born during a full moon by looking at old records
multiple-group time series design:
A design in which a series of measures are taken on two or more groups both before and after a treatment. -Converting that single-group time-series design to a multiple-group time-series design would involve finding a comparison group a state that did not crack down on speeding during the same time period. Campbell (1969) found four other states that did not crack down on speeding at the same time as CT. As can be seen, the fatality rates in the states used as the control group remained fairly stable, while the fatality rates in Connecticut decreased. Based on these data, Campbell concluded that the crackdown had the desired effect on fatality rates.
single-group posttestonly design
A design in which a single group of participants is given a treatment and then tested. -simplest quasi-experimental design -Caution: This lack of comparison is the problem with this type of design: How can we claim a method is better when we cannot compare the results for the group who participated with the results for any other group or standard?
single-group time-series design
A design in which a single group of participants is measured repeatedly before and after a treatment. -CT study of car crash fatalities over a number of years
single-group pretest/posttest design
A design in which a single group of participants takes a pretest, then receives some treatment, and finally takes a posttest.
nonequivalent control group pretest/post-test design:
A design in which at least two nonequivalent groups are given a pretest, then a treatment, and finally a post-test. -Ex: Results showed that after the introduction of television in Notel, there was a significant decline in participation in community activities and a significant increase in aggressive behavior in children.
nonequivalent control group post-test-only design
A design in which at least two nonequivalent groups are given a treatment and then a posttest measure.
ABAB reversal design
A design in which baseline and independent variable conditions are reversed twice. -deaf girl biting experiment
small-n design
A design in which only a few participants are studied.
single-case design
A design in which only one participant is used.
positive correlation
A direct relationship between two variables in which an increase in one is related to an increase in the other and a decrease in one is related to a decrease in the other. -Usually height and weight; High school GPA and college GPA
scatterplot
A figure that graphically represents the relationship between two variables. -Graphically represents the correlation coefficient.
Informed consent form:.
A form given to individuals before they participate in a study to inform them of the general nature of the study and to obtain their consent to participate -The informed consent form typically describes the nature and purpose of the study. However, to avoid compromising the outcome of the study, the researcher obviously cannot inform participants about the expected results. Thus informed consent forms often make only broad, general statements about the nature and purpose of a study.
placebo group
A group or condition in which participants believe they are receiving treatment but are not.
floor effect
A limitation of the measuring instrument that decreases its ability to differentiate between scores at the bottom of the scale. -measuring rats in pounds
ceiling effect
A limitation of the measuring instrument that decreases its ability to differentiate between scores at the top of the scale. -measuring elephants on a bathroom scale
action research
A method in which research is conducted by a group of people to identify a problem, attempt to resolve it, and then assess how successful their efforts were. Researchers are also participants, which can be a problem. -"If you want something done, do it yourself." -3 phases: looking, thinking, action
random selection
A method of generating a random sample in which each member of the population is equally likely to be chosen as part of the sample.
correlational method:
A method that assesses the degree of relationship between two variables.
focus group interview
A method that involves interviewing 6 to 10 individuals at the same time.
field studies
A method that involves observing everyday activities as they happen in a natural setting. -the observer is directly involved with those that are being observed.
interview
A method that typically involves asking questions in a face-to-face manner that may be conducted anywhere.
rating scale
A numerical scale on which survey respondents indicate the direction and strength of their response.
skeptic
A person who questions the validity, authenticity, or truth of something purporting to be factual. A good thing in science.
reactivity
A possible reaction by participants in which they act unnaturally because they know they are being observed.
hypothesis
A predictionregarding the outcome of a study that often involves the relationship between two variables.
equal unit size
A property of measurement in which a difference of 1 is the same amount throughout the entire scale.
absolute zero
A property of measurement in which assigning a score of zero indicates an absence of the variable being measured.
identity
A property of measurement in which objects that are different receive different scores.
magnitude
A property of measurement in which the ordering of numbers reflects the ordering of the variable.
double-barreled question
A question that asks more than one thing.
loaded question
A question that includes nonneutral or emotionally laden terms.
leading question
A question that sways the respondent to answer in a desired manner.
negative relationship:
A relationship between two variables in which an increase in one is accompanied by a decrease in the other. -altitude and air temperature
positive relationship:
A relationship between two variables in which an increase in one is accompanied by an increase in the other. -the taller someone is, the heavier they get.
alternate-forms reliability
A reliability coefficient determined by assessing the degree of relationship between scores on two equivalent tests.
test/retest reliability
A reliability coefficient determined by assessing the degree of relationship between scores on the same test administered on two different occasions.
split-half reliability
A reliability coefficient determined by correlating scores on one half of a measure with scores on the other half of the measure.
interrater reliability
A reliability coefficient that assesses the agreement of observations made by two or more raters or judges. Interrater reliability = Number of agreements / Number of possible agreements x 100
socially desirable response
A response that is given because a respondent believes it is deemed appropriate by society.
random sample
A sample achieved through random selection in which each member of the population is equally likely to be chosen.
representative sample
A sample that is like the population.
stratified random sampling:
A sampling technique designed to ensure that subgroups or strata are fairly represented. -Ex: If a population is 70% women and 30% men, the survey must reflect that.
cluster sampling
A sampling technique in which clusters of participants that represent the population are used.
convenience sampling
A sampling technique in which participants are obtained wherever they can be found and typically wherever it is convenient for the researcher. -standing outside the library and surveying the first 100 college students you see
nonprobability sampling
A sampling technique in which the individual members of the population do not have an equal likelihood of being selected to be a member of the sample. -2 kinds: Convenience and Quota Sampling
quota sampling
A sampling technique that involves ensuring that the sample is like the population on certain characteristics but uses convenience sampling to obtain the participants.
ratio scale:
A scale in which in addition to order and equal units of measurement there is an absolute zero that indicates an absence of the variable being measured.
ABA reversal design
A single-case design in which baseline measures are taken, the independent variable is introduced and behavior is measured, and the independent variable is then removed (a return to baseline condition) and measures are taken again. -The problem with this design is an ethical one. If the treatment helped to improve the participant s life in some way, it is not ethical to end the experiment by removing the treatment and possibly returning the participant to his or her original state. Thus a further improvement over the ABA design is the ABAB design.
multiple-baseline design across situations
A single-case design in which measures are taken at baseline and after the introduction of the independent variable at different times across multiple situations. -boy crying in class with colored slips of paper being taken away
multiple-baseline design across behaviors:
A single-case design in which measures are taken at baseline and after the introduction of the independent variable at different times across multiple behaviors. -Imagine that a teacher wanted to minimize the number of problem behaviors emitted by a student during the school day.
reversal design
A single-case design in which the independent variable is introduced and removed one or more times; a design with only one participant;
multiple-baseline design
A single-case or small-n design in which the effect of introducing the independent variable is assessed over multiple participants, behaviors, or situations. We control for confounds not by reverting to baseline after each treatment as in a reversal design but by introducing the treatment at different times across different people, behaviors, or situations.
multiple-baseline design across participants:
A small-n design in which measures are taken at baseline and after the introduction of the independent variable at different times across multiple participants. -Ex: 3 French students threatened at separate times with extra study sessions if they failed a quiz. All 3 improved at the respective time.
conceptual replication
A study based on another study that uses different methods, a different manipulation, or a different measure.
systematic replication
A study that varies from an original study in one systematic way—for example, by using a different number or type of participants, a different setting, or more levels of the independent variable.
personal interview
A survey in which the questions are asked face to face.
telephone survey
A survey in which the questions are read to participants over the telephone.
checklist
A tally sheet on which the researcher records attributes of the participants and whether particular behaviors were observed.
sampling bias
A tendency for one group to be overrepresented in a sample.
regression to the mean
A threat to internal validity in which extreme scores upon retesting tend to be less extreme, moving toward the mean. This is a threat to internal validity. -also known as statistical regression -Ex: People retaking an SAT and doing much worse. 1st score was result of luck. -Ex: Athletes on the cover of Madden
subject (participant) effect:
A threat to internal validity in which the participant, consciously or unconsciously, affects the results of the study.
experimenter effect
A threat to internal validity in which the experimenter, consciously or unconsciously, affects the results of the study. -possibly with a smile or frown or a biased response that affects the subject -aka experimenter bias
static item
A type of item used on a checklist on which attributes that do not change are recorded. -Ex: Gender, race, age of participants
action item
A type of item used on a checklist to note the presence or absence of behaviors. -Ex: types of stops at a stop sign (rolling, complete, none)
Likert rating scale
A type of numerical rating scale developed by Rensis Likert in 1932.
qualitative research
A type of social research based on field observations that is analyzed without statistics. -Researchers using this approach may not necessarily believe that there is a single truth to be discovered but rather that there are multiple positions or opinions and that each have some degree of merit.
restrictive range (type of misinterpretation)
A variable that is truncated and has limited variability. (see search pg 162) -One or more of the variables is truncated or restricted, and the opportunity to observe a relationship is minimized. -If SAT scores are restricted (limited in range), the correlation between SAT and GPA appears to decrease.
mail survey
A written survey that is self-administered.
population:
All the people about whom a study is meant to generalize.
double-blind experiment
An experimental procedure in which neither the experimenter nor the participant knows the condition to which each participant has been assigned; both parties are blind to the manipulation.
case study method:
An in-depth study of one or more individuals. - involves simply describing the individuals being studied.
reliability
An indication of the consistency or stability of a measuring instrument.
magnitude
An indication of the strength of the relationship between two variables. -To sum up, whereas a correlation coefficient of 1.00 represents a perfect relationship, a coefficient of 0 indicates no relationship between the variables.
validity
An indication of whether the instrument measures what it claims to measure.
placebo
An inert substance that participants believe is a treatment.
negative correlation
An inverse relationship between two variables in which an increase in one variable is related to a decrease in the other and vice versa. -As age increases, sight and hearing usually decrease
theory:
An organized systemof assumptions and principles that attempts to explain certain phenomena and how they are related.
confound
An uncontrolled extraneous variable or flaw in an experiment. -Because of the weaknesses in quasi-experimental designs, we can never conclude that the independent variable definitely caused any of the observed changes in the dependent variable.
Survey
Another means of collecting data
person-who argument
Arguing that a well established statistical trend is invalid because we know a "person who" went against the trend.
random assignment:
Assigning participants to conditions in such a way that each has the same probability as all others of being placed in any condition. -should minimize or eliminate differences between groups
Description (Goals of Science)
Carefully observing behavior in order to describe it.
partially open-ended questions
Closed-ended questions with an openended "Other" option.
Stanley Milligram's study
Ethical questions; teachers inflicting pain on students
laboratory observation:
Observing the behavior ofhumans or other animals in a contrived and controlled situation, usually the laboratory.
narrative records
Full narrative descriptions of a participant's behavior. -can be direct by taking notes or indirect from video recording
No Relationship
Graph shows no meaningful relationship between two variables. -Example: intelligence and weight
Explanation (Goals of Science)
Identifying the causes that determine when and why a behavior occurs. -To explain a behavior, we need to demonstrate that we can manipulate the factors needed to produce or eliminate it.
Prediction (Goals of Science)
Identifying the factors that indicate when an event or events will occur.
Deception
Lying to the participants concerning the true nature of a study because knowing the true nature of the study might affect their performance.
systematic empiricism
Making observations in a systematic manner in order to test hypotheses and refute or develop a theory.
observational method:
Making observations ofhuman or other animal behavior.
Personality Tests
Many personality tests are also affective self-report measures; they are designed to measure aspects of an individual s personality and feelings about certain things.
Tests
Measurement instruments used to assess individual differences in various content areas. -Psychologists frequently use two types of tests: personality tests and ability tests.
physical measures
Measures of bodily activity such as pulse or blood pressure that may be taken with a piece of equipment.
behavioral measures
Measures taken by carefully observing and recording behavior. -anything a person or animal does
naturalistic observation:
Observing the behavior of humans or other animals in their
public verification
Presenting research to the public so that it can be observed, replicated, criticized, and tested.
Debriefing
Providing information about the true purpose of a study as soon after the completion of data collection as possible.
survey method:
Questioning individuals on a topic or topics and then describing their responses.
closed-ended questions
Questions for which participants choose from a limited number of alternatives.
open-ended questions
Questions for which participants formulate their own responses.
empirically solvable problems:
Questions that are potentially answerable by means of currently available research techniques.
demographic questions
Questions that ask for basic information such as age, gender, ethnicity, or income.
Reliability vs. Validity
Reliability measures consistency Validity measures truthfulness (Validity always measures reliability- not the other way around though)
exact replication
Repeating a study using the same means of manipulating and measuring the variables as in the original study.
quasi-experimental method:
Research that compares naturally occurring groups of individuals; -the variable of interest cannot be manipulated.
Cognition
Researchers who study cognition are interested in how humans process, store, and retrieve information; solve problems; use reasoning and logic; make decisions; and use language.
Scientific Research
Scientific research has three basic goals: (1) to describe behavior, (2) to predict behavior, and (3) to explain behavior. All of these goals lead to a better understanding of behavior and mental processes.
APA Principles Covering Treatments
See Table 4.1 around PDF page 77 See Table 4.2 on animal treatment
principle of falsifiability
Stating a scientific theory in such a way that it is possible to refute or disconfirm it.
Minimal Risk in a study
Studies in which participants are asked to fill out paper-and-pencil tests such as personality inventories or depression inventories -Other examples of minimal risk studies are most research projects on memory processes, problem-solving abilities, and reasoning in which participants are asked simply to answer questions. -anything similar to normal life stress -informed consent not necessary but recommended
undisguised observation
Studies in which the participants are aware that the researcher is observing their behavior.
disguised observation
Studies in which the participants are unaware that the researcher is observing their behavior.
participant observation
Studies in which the researcher actively participates in the situation in which the research participants are involved.
nonparticipant observation
Studies in which the researcher does not participate in the situation in which the research participants are involved.
causality (type of misinterpretation)
The assumption that a correlation indicates a causal relationship between two variables. -As we know, a correlation between two variables indicates only that they are related, that is, they vary together.
Curvilinear Relationship (type of misinterpretation)
The curved nature of the relationship decreases the observed correlation coefficient. -Ex: As arousal increases, performance increases up to a point; as arousal continues to increase, performance decreases.
construct validity
The degree to which a measuring instrument accurately measures a theoretical construct or trait that it is designed to measure.
criterion validity
The extent to which a measuring instrument accurately predicts behavior or ability in a given area.
face validity
The extent to which a measuring instrument appears valid on its surface.
content validity
The extent to which a measuring instrument covers a representative sample of the domain of behaviors to be measured.
ecological validity
The extent to which research can be generalized to real-life situations.
internal validity
The extent to which the results of an experiment can be attributed to the manipulation of the independent variable rather than to some confounding variable. -Quasi-experimental designs lack internal validity.
external validity
The extent to which the results of an experiment can be generalized (like to all populations, etc.)
control group:
The group of participants who do not receive any level of the independent variable and serve as the baseline in a study.
experimental group:
The group of participants who receive some level of the independent variable.
sample:
The group of people who participate in a study.
alternative explanation:
The idea that another uncontrolled, extraneous variable may be responsible for an observed relationship. Ex: Greek students come from rich families and have money for beer- so they drink more.
nonmanipulated independent variable
The independent variable in a quasi-experimental design in which participants are not randomly assigned to conditions but rather come to the study as members of each condition. -Also known as subject variables (or participant that cannot be changed such as ethnicity, gender, age, or political affiliation)
directionality (type of misinterpretation with causality)
The inference made with respect to the direction of a causal relationship between two variables.
expectancy effects
The influence of the researcher's expectations on the outcome of the study.
third-variable problem (type of misinterpretation)
The problem of a correlation between two variables being dependent on another (third) variable. -Ex: Can you think of other ways in which individuals who use contraceptives and who have a large number of appliances might be similar? Education is a possible third variable.
basic research
The study of psychological issues in order to seek knowledge for its own sake. much of what started out as basic research has eventually led to some sort of application.
applied research
The study of psychological issues that have practical significance and potential solutions.
interviewer bias
The tendency for the person asking the questions to bias the participants' answers.
response bias
The tendency to consistently give the same answer to almost all of the items on a survey.
independent variable:
The variable in a study that is manipulated by the researcher.
dependent variable:
The variable in a study that is measured by the researcher.
Observed Score
True Score + Measurement error
Reliability
True Score / True score + error score -ideally this would equal 1. The greater the error, the lower the reliability score
Ability Tests
Two types: Aptitude- someone's potential to do something Achievement- measure competence in an area
Quasi-Experimental Method
Typically one nonmanipulated independent variable and one measured dependent variable Conclusions: Systematic differences have been observed between two or more groups, but we cannot say that the nonmanipulated independent variable definitely caused the differences. Cautions: Due to confounds inherent in the use of nonmanipulated independent variables, there may be alternative explanations for the results.
self-report measures
Usually questionnaires or interviews that measure how people report that they act, think, or feel. -Cognitive self-report measures ask individuals to report what they think about something. -Affective self-report measures ask individuals to report how they feel about something.
Positive Relationship
Variables increase and decrease together -Example: Smoking and cancer
Curvilinear
Variables increase together up to a point and then as one continues to increase, the other decreases -like in a U-shaped scatterplot -For example, memory and age
discrete variables
Variables that usually consist of whole number units or categories and are made up of chunks or units that are detached and distinct from one another.
continuous variables
Variables that usually fall along a continuum and allow for fractional amounts.
knowledge via authority
When we accept what a respected or famous person tells us. Accepting the word of an authority figure may be a reliable and valid means of gaining knowledge but only if the individual is truly an authority on the subject.
experimental method:
a research method that allows a researcher to establish a cause-and-effect relationship through manipulation of a variable and control of the situation.
probability sampling
a sampling technique in which each member of the population has an equal likelihood of being selected to be part of the sample.
control group
baseline or standard conditon -one of the independent variable groups
knowledge via superstition
acquiring knowledge based on subjective feelings, belief in chance, or belief in magical events. ex: 7 years of bad luck or that the number 13 is unlucky. -As such, they represent a means of gaining knowledge that is neither reliable nor valid.
Naturalistic observation
aka Field observation involves watching people or animals in their natural habitats
Laboratory Observation
aka Systemic Observation; An observational method that is usually less costly and time-consuming and affords more control
Case Study Method
an in-depth study of one or more individuals, groups, social settings, or events in the hope of revealing things that are true of all of us. -Caution: Because of these limitations, case study research should be used with caution, and the data should be interpreted for what they are observations on one or a few possibly unrepresentative individuals, groups, settings, or events.
Psychobiology
combines biology and psychology. Researchers in this area typically study brain organization or the chemicals in the brain (neurotransmitters).
unstandardized interview
completely unstructured in that there is no set order to the questions, nor a set wording to the questions. The questions are more spontaneous and free flowing.
Psychotherapy
designed to assess whether a therapy is really effective in helping individuals.
standardized interview
formal in structure and questions are asked in specific order
Knowledge via empiricism
gaining knowledge through objective observation and the experiences of the senses. An individual who says that I believe nothing until I see it with my own eyes is an empiricist. Doubting Thomas
semistandardized interview
has some structure to it, but the wording of the questions is flexible, the level of the language may be modified, and the interviewer may choose to answer questions and provide further explanation if requested.
Social Psychology
how we view and affect one another. Research in this area combines the disciplines of psychology and sociology, in that social psychologists are typically interested in how being part of a group affects the individual.
knowledge via science
involves a merger of rationalism and empiricism. Scientists collect data (make empirical observations) and test hypotheses with these data (assess them using rationalism). By merging rationalism and empiricism, we have the advantage of using a logical argument based on observation.
knowledge via tenacity
involves hearing a piece of information so often that you begin to believe it is true and then, despite evidence to the contrary, clinging stubbornly to that belief. Ex: political campaigns
knowledge via rationalism
logical reasoning. All humans are mortal; I am a human; Therefore I am mortal. Logic deals only with the form of the syllogism and not its content. Obviously, researchers are interested in both form and content.
control:
manipulating the independent variable in an experiment or any other extraneous variables that could affect the results of a study. -manipulate the independent variable and limiting (or controlling) other variables
demand characteristics
real or imagined cues from the researcher as perceived by the participant
experimental group
receives some level of the independent variable -one of the independent variable groups
Human Development
research on human physical, social, and cognitive development. This work might involve research from the prenatal development period throughout the life span to research on the elderly (gerontology).
placebo effect
the improvement may be due not to the effects of the treatment but to the participant s expectation that the treatment will have an effect.
illusory correlation
the perception of a relationship that does not exist. More babies are not born when the moon is full, nor are couples more likely to conceive after adopting
knowledge via intuition
we have knowledge of something without being consciously aware of where it came from. Ex: "I don t know, it just came to me, and I know it s true."
artificiality criticism
we need to exercise caution when generalizing from the laboratory setting to the real world
a psychologist is a scientist
what makes something a science is not what is studied but how it is studied...what defines science is how something is studied. Science is a way of thinking about and observing events in order to achieve a deeper understanding of them. Psychologists apply the scientific method to their study of human beings and other animals.