Data collection Flashcards
(17 cards)
Explain
Population
The whole set of items of interest
Explain
Census
Observes or measures
every member of a population
Explain
Sample
Selection of observations from a subset of the population
Explain
Sampling frame
A numbered list of sampling units
Explain
Sampling unit
Individual units of a population
Explain
Random sample
A random sample of size n. Every sample of size n has an equal chance of selection.
Explain
Systematic sample
The required elements are chosen at regular intervals
from an ordered list.
Explain
Stratified sample
The population is divided into mutually exclusive strata. Random samples are taken from each.
Explain
Quota sample
The researcher selects a sample that reflects
characteristics of the whole
Explain
Opportunity sample
The researcher takes the sample from people available at the time.
Explain
Quantitative variables
Variables associated with numeric data
Explain
Continuous variable
Continuous variables can take any value
Explain
Discrete variable
Discrete variables can only take specific values from a range
Explain
Qualitative variables
Data associated with non-numerical observations
Explain
Class
The data is resented in a group frequency table. The specific values are not shown.
Explain
Class boundary
The minimum and maximum values of a class
Explain
Mid-point
The average of the class boundaries
