Abnormal Psychology Ch. 2

negative correlation

-inverse correlation -negative correlation coefficient (variables are opposite) ex. higher temp, less clothes

positive correlation

-positive direction -variables change in the same way ( ^^ .. both up, both down)

Limitations of case studies

-reported biased observers -subjective evidence -internal validity -external validity -cant really be replicated

How are case studies helpful?

-source of new ideas -may offer tentative support (for a theory) -challenge a theory's assumptions -show value of new therapeutic techniques -opportunity to study unusual problems

analogue experiment

a research method in which the experimenter produces abnormal-like behavior in laboratory participants & then conducts experiments on the participants -often use animals as participants

experiment

a research procedure in which a variable is manipulated & the manipulation's effect on another variable is observed

correlational method

a research procedure used to determine how much events or characteristics vary along with eachother

placebo therapy

a sham treatment that the participant in an experiment believe to be genuine

blind design

an experiment set up so participants do not know whether they are in the experimental or control group

case study

detailed description\account of a person's life and their psychological problems -describes a person's history, present circumstances, and symptoms

nomothetic

general -understanding of nature, causes, and treatments of abnormality

random sample

group of people where every member of the larger population has en = chance of being in the sample

population

group of people you're interested in studying

control group

group of research participants that are NOT exposed to the independent variable under investigation but whose experience is like the people who are exposed to the i.v.

longitudinal studies

high-risk\developmental studies -a study that observes the same participants on many occasions over a long period of time

hypotheses

hunch\predictions that certain variables are related in certain ways

confound

in an experiment, a variable other than the independent variable that is also acting on the dependent variable -causing observed change

independent variable

is manipulated!

dependent variable

measured in effect of independent variable

Natural experiment

nature itself manipulates the independent variable (not an experimenter) and the experimenter observes the effects -used for studying the psychological effects of unusual and unpredictable events (floods, earthquakes, etc.) -participants are selected by accident\"fate" rather than by the investigators design

.-16 (correlation)

negative & weak (closer 0 than 1 or -1)

double blind study

neither researcher nor participants know who's in control or experimental group

ABAB \ reversal design experiment

participant's runs are measured & compared not only during baseline period (condition A) -after introduction of the independent variable (condition B) -but also after the independent variable has been removed (condition A again) - and after it has been reintroduced one more time (condition B again) -ABAB design= participant is compared with him\herself under diff. conditions rather than with control participants

placebo effect

people's expectations that something will happen. ~ Ex. given alcohol that's nonalcoholic, people act drunk (expectations influence outcome)

.92 (correlation)

positive & strong ( ^^, close to 1)

single-subject experiment

single participant is observed both before and after the manipulation of an independent variable

epidemiological research

statistical research; shows trends, risk factors -a study that measures the incidence and prevalence of a disorder in a given population

internal validity

the accuracy with which a study can pinpoint one of the various possible factors as the cause of a phenomenon

correlation

the degree to which events\characteristics vary along with each other

external validity

the degree to which the results of a study may be generalized beyond that study

incidence

the number of new cases that emerge in a particular population -over a specific period of time

experimental group

the participants who are exposed to the independent variable under investigation -->compared to control group.

scientific method

they collect and evaluate info. through careful observations. these observations in turn enable them to pinpoint & explain relationships btwn. variables (the process of systematically gathering careful observations to gain an understanding)

prevalence

total # of cases in the population during a given time period; includes both existing & new cases

quasi-experimental design

~AKA: Mixed design -researchers do NOT randomly assign participants to control & experimental groups but instead make use of groups that already exist in the world at large -ex. compare people with history of child abuse v. people who did not