Chapter 12 Flashcards
(29 cards)
Example of a target population
people suffering from diagnosed depression
When are target populations important?
when you have a population in mind
Study population
operationally define target pop in terms of some manifest variable, like depression diagnosis
Research Sample
subset of study population who become participants
Simple Random Sampling
Everyone in sampling frame has equal chance of being selected
Stratified Random Sampling
Demographic characteristics, gender, ethnicity, class, then randomly assign from those categories
Restriction of probability sampling
can typically only use with relatively small study populations
Multistage cluster sampling
randomly sample cluster, then random sample from that, etc.
Non probability sampling is:
More common, convenience samples
Haphazard research sampling
any convenient research participant
External validity of convenience samples is..
controversial, these samples need to be replicated many times
Purposive sampling
selecting participants because they are viewed as representatives of target pop
Snowball sampling
individuals selected to participate then choose people like themselves to participate
People who sign up at the start of the term are..
highly conscientiousness
no show rates increase or decrease across the term?
increase
Kraemer and Thiemann 6 “Facts of life”, determining sample size
More stringent sig level greater sample size needed
2 tailed tests require larger sample size
smaller critical effect size larger sample size
larger power required the larger necessary sample size
smaller sample size means smaller power and higher chance type 2 error
sample size of 20 or fewer have high risk of failure
Coherence
subjects must experience the setting as logical, must make sense
simplicity
keep it simple, the more complex the greater likelihood that something will go wrong
psychological involvement
should engage subjects
experimental realism
how engaging is research situation, level of psychological involvement
mundane realism
how artificial the research situation is, ecological validity
Consistency
keep it all standard
effective instructions
be clear, get their attention, check understanding
Debugging procedures (3)
colleagues read it, rehearse, and pilot study
