U1 One-Variable Statistics Flashcards
continuous variable
can have any value w/ in a given range
discrete variable
can only have certain values (usually whole #s)
simple random sampling
every member of pop has equal chance of being chosen
systematic sampling
selecting members at regular intervals
stratified sampling
surveying members from different subgroups at equal portions
Cluster sampling
- surveying specific related groups to represent pop
- naturally divided
multi-stage sampling
- several lvls of random sampling
- ex. country>province>district>highschool>classes
voluntary-response
open invitation for pop to participate
convenience sample
selected because of access reasons
bias
when Data does not reflect the pop
unintentional bias
introduced in poor methodology
intentional bias
used to manipulate stats for certain POV
sampling bias
does not accurately represent pop
response bias
elicits false or misleading answers
measurement bias
- methodology under/over estimates results
- may contain unnecessary info