questions well answered
explanatory variable - correct answer ✔✔
response variable - correct answer ✔✔ the quantitative or qualitative variable for which the
experimenter wishes to determine how its value is affected by the explanatory value
define treatment - correct answer ✔✔ any combination of the values of the factors
(explanatory variables)
factor - correct answer ✔✔ a variable whose effect on the response variable is to be assessed
by the experimenter
confounding - correct answer ✔✔ the effect of two factors cannot be distinguished
statistics - correct answer ✔✔
parameter - correct answer ✔✔
define statistics - correct answer ✔✔
observational study - correct answer ✔✔ measures the value of response variable w/o
attempting to influence the response or explanatory variable
, designed experiment - correct answer ✔✔ researcher assigns individuals to a certain group,
intentionally changes the value of an explanatory variable and records the value
cross-sectional - correct answer ✔✔ collect info @ specific point in time, or over short period of
time
case-control (retrospective) - correct answer ✔✔ require individuals to look back in time or
records. individuals with certain traits matched with ones who don't
cohort (prospective) - correct answer ✔✔ group of individuals to participate in study, then
observed over time. characteristics recorded.
stratified sample - correct answer ✔✔ dividing the population into non-overlapping groups
called strata. and then getting a simple random sample from each strata. individuals in each
strata should be similar in some way
convenience sample - correct answer ✔✔ has sampling bias bc individuals arent chosen
through random sample
simple random sample - correct answer ✔✔ ex: out of 250 employees, only 25 are chosen.
ex: n=3, N=6
1, 2, 3 ... 1, 2, 4 ... 1, 2, 5 ... etc
systematic sample - correct answer ✔✔ selecting every Kth individual from the population.
doesnt require a frame
K = N/n
N: population
n: sample