final exam Flashcards
Why can’t we say that we have “proven” anything?
because they use that term to refer to the result of a logical deduction. In this rigorous sense, scientific theories can never be proven; they can only be confirmed. (weight of evidence)
can research explain all cases?
no, because research is probabilistic, but can explain a portion of the cases
research is done on a sample, so… there is always some error
sampling error
small chance that we made error, so we set probability to p
statistics
something that varies/changes
variable
factor in an experiment that researchers manipulate so that they can determine its effect, factor in a controlled experiment that is deliberately changed; also called manipulated variable
independent variable
the reaction to the independent variable changing
dependent variable
does not change (only has one level) or is kept the same
constant
carefully define concept at theoretical level (conceptual definition)
concept variable = construct
a variable of interest, stated at an abstract level, usually defined as part of a formal statement of a psychological theory
construct
to turn a conceptual definition of a variable into a specific measured variable or manipulated variable in order to conduct a research study
operationalize
reasonable, accurate, justifiable
validity
how consistent your results are
reliability
you are ONLY able to make casual claims with a…
true experiment
what 3 criteria must you adhere to have a true experiment?
random sample, random assignment, and an IV with 2 levels at least
why do researchers use random assignment to treatment groups?
increases internal validity
used only in experimental designs to assign participants to groups at random (increases internal validity)
random assignment
everybody has equal chance of being chosen (increases external validity)
random selection
A “false positive” result from a statistical inference process, in which researchers conclude that there is an effect in a population when there really is none
Type I error
a “miss” in the statistical inference process, in which researchers conclude that there is no effect in a population when there really is one
Type II error
a variable of interest, stated at an abstract, or conversational, level
conceptual variable
what are three common measures?
- self-report
- observational measures
- physiological measures
concepts can be operationalized in lots of different ways so…
it is a good idea to use more than one concept to see if they correlate
why are scatterplots used?
compile data after test (ex. IQ)
how can we use correlation coefficient “r” to quantify reliability?
slope direction, strength of relationship
how do we interpret “r”?
r = +- 1.0
how do validity and reliability relate to one another?
something can be reliable and not valid - however, you can not have something valid that is unreliable too
what are the different types of validity?
face, content, criterion- known groups evidence; convergent and discriminant
how can question order impact someone’s answers? what can be done about it?
questions asked earlier in the survey may influence the way a person answers a question later in the survey
how can you get people to respond honestly and/or accurately?
conduct pilot tests or focus groups early in the survey
a shortcut respondents may use to answer items in a long survey, rather than responding to the content of each item
response set
examples of response sets
non differentiation, acquiescence or yea sayers, nay sayers, fence sitting
observer bias- how can it be addressed?
systematic errors in observation that occur because of an observer’s expectations
what are observer effects? (also known as expectancy effects)?
bright vs. dull maze rats, clever Hans-researcher subtly communicated to participants “how they should behave”
How do we prevent observer bias/expectancy?
use masked or blind designs, video or audio record, use more than one observer to assess inter-rater reliability, make sure coding/observing system is well thought out, observers well trained
What can be done about reactivity?
unobstrusive observations and deception
extent to which research results apply to a range of individuals not included in the study
generalizability
extent to which we can generalize findings to real-world settings
external validity
why are generalizability and external validity important for frequency claims?
frequency claims need random sample; when a random sample can’t be used, assess whether potential bias will have impact on results; casual and association claims make external validity a lower priority
population vs. sample
whole set vs part of population
simple random sample, cluster samples, multistage samples, stratified random samples, oversampling, systematic sampling, weighting - combo of sampling techniques
probability sampling
convenience sampling, purposive sampling, snowball, and quota
non-probability sampling