unit 2 exam Flashcards
what is a true experiement?
-researcher manipulates an independent variable
-tests whether the manipulation influences a dependent variable
what is a correlational study?
-researcher does not manipulate independent variable
-examines relationship b/w variables they chose to examine
what is an Ex Post Facto?
-special case of correlational study
-researcher compares groups of individuals who differed prior to their participation of in the study
what is a variable?
-something that varies, if participants are all the same it is not a variable
what is true about variables?
-the levels of a variable are the different specific possibilities (ex. age, reaction time)
-each variable has at least two possibilities/alternatives
what do levels represent in terms of variables?
number of alternatives being examined or manipulated in the study (ex. high noise vs low noise = 2 levels)
what is an independent variable?
-the variable being manipulated
-experimenter manipulated (true experiment)
-experimenter selected (subject variable, ex post facto)
what is a dependent variable?
variable whose reaction is being observed/measured
what is true about correlational designs?
it is not clear which is the independent and dependent variables
what is an operational definition?
a statement of the operations necessary to produce and measure a concept or construct
true or false: all variables in psychological research must be operationally defined.
true
what are these examples of?
-people with panic disorder vs. people with no psychiatric disorder
-individuals in noise condition vs. individuals in quiet conditon
contrast
true or false: you should attempt to draw an inference (conclusion) on the basis of the contrast
true
in an experiment, how should you hold conditions constant?
control for everything except the independent variable about which you want to draw an inference
what is an extraneous/confounding variable?
any variable you are not interested in that is not controlled for
what are the two types of controls?
1.between-subject design: there is an experimental and a control group
2.within-subject design: subjects serve as own control by comparing a single group of individuals under two+ different conditions
what is a placebo?
-an intervention that is presented to the participant as though it is the real intervention that’s expected to have an impact
can there be a placebo in psychotherapy research?
it is unclear because part of impact is attention from a therapist
what is experimenter bias?
the results of a study being influenced by the experimenter’s unconscious belies/biases
what are demand characteristics?
subtle cues in a research study that can unintentionally signal to participants what the researcher is expecting of them or hoping to find
what can be used to limit or prevent experimenter bias and demand characteristics?
placebos
what is block randomization/random blocks technique?
rank order all participants, take groups of individuals with adjacent rank ordered scores and then randomly assign groups
which type of group membership assignment poses the greatest risk of group differences due to bad luck?
random assignment
which type of group membership assignment poses the smallest risk of group differences due to bad luck?
matching