week four | qualitative and quantitative Flashcards
describes trends or explains relationships among variables
quantitative research
hypothesis verification
goal of quantitative research
focus on a class of events and attempts to specify the conditions that seem common to those events
nomothetic explanation
experimental, correlational, and survey
quantitative research designs
technique in which information is gathered from respondents. measures what people say and not what people do
survey research
study over time, observes trends in the same population
longitudinal
study at one point in time, studies current attitudes and trends
cross-sectional
fixed set of alternatives that are all possible, relevant options determined in advance, ease of data handling
closed-ended
respondents develop their own responses, thus response options are not predictable, complex data handling
open-ended
two basic forms of a survey
a questionnaire and an interview
the basic objects on which the experiment is done (when these are human, they are called subjects)
units
measure characteristic of a unit that is capable of taking on more than one value
variable
variable whose changes are being measured
dependent
variable that is being manipulated, also called a factor
independent
influences on the dependent variable from a source other than the independent variable
extraneous variables
helps to control for extraneous variables, assignment of subjects to experimental or control conditions is equally likely by change
random assignment
systematically selecting homogenous sample from a heterogenous population and randomly assigning sample to experimental or control conditions
holding variables constant
experimental group members are paired with similar control group members for data analysis
matching participants
combination of matching and randomization, subjects are first matched on one or more key variables in order to form homogenous groupings. members of each block are then randomly assigned to the experimental or control conditions.
blocking variables
any specific condition applied to the units
treatment
both subjects and those who evaluate the outcome are ignorant of which treatment was given
double-blind technique
whether the independent variable actually produces the effect that it appears to have had on the dependent variable, controlling for extraneous variables
internal validity
refers to the capacity to generalize casual inferences to other times, settings, or groups of people
external validity
subjects are observed after treatment was delivered, randomization or control groups are not used
pre-experimental designs