Term | Definition |
variable | characteristic or attribute that can assume different values |
data | values of the variables |
random variable | variables that have their value determined by chance |
data set | collection of data values |
data value -- datum | each value of the data set |
probability | the chance of an event occuring |
population | consists of all subjects being studied |
sample | group of subjects selected from a population |
hypothesis testing | decision-making process for evaluating claims about a population based on info from samples |
independent variable (exploratory) | a variable in correlation and regression analysis that can be controlled or manipulated |
dependent event (outcome, resultant) | events for which the outcome or occurrence of the first event affects the outcome or occurrence of the second event in such a way that the probability is changed |
true vs. quasi experiments | one case where the subjects are assigned to groups randomly while the other case is where subjects are in intact groups |
confounding variable | a variable that influences the outcome variable but can't be separated from the other variables that influence the outcome variable. |
Hawthorne effect | an effect on an outcome variable caused by the that subjects of the study know that they are participating in the study |
control group | a group in an experimental study that isn't given any special treatment |
treatment group | a group in an experimental study that has received some kind of treatment |
margin of error | a usually small amount that is allowed for in case of miscalculation or change of circumstances |
margin of error interval | the interval calculated after finding the amount of miscalculation or change of circumstances |
biased question | a question constructed badly and is asked in such a way that the respondent can understand it wrongly and if can favor a certain answer |
unbiased question | questions that are read in a way that they don't influence the respondents or provide info. which may color the opinions of the respondents |
sequential sampling | used in quality control; successive units taken from the production line and sampled to ensure the product meets the standards |
double sampling | a sampling method in which a very large population is given a questionnaire to determine those who meet the qualifications for a study; the questionnaire is reviewed, a second smaller population is defined, and a sample is selected from this group |
multistage sampling | a sampling technique that uses a combination of sampling methods |