Chapter 1 Flashcards
(27 cards)
What is population?
The entire set of items (sampling units) in the group being studied
What is census?
Measuring every member of a population
What is an advantage of a census?
It’s accurate
What is a disadvantage of a census?
- expensive
- some testing destroys the item
What is a sampling frame?
List of sampling units
What are the types of random sampling?
- simple random sampling
- systematic sampling
- stratified sampling
What is a simple random sampling?
Equal chance of being selected, use random number generator alongside sampling frame
What is an advantage of simple random sampling?
It’s bias free
What is a disadvantage of simple random sampling?
Sampling frame required
What is systematic sampling?
Takes every kth unit, pick a random number between 1 and k for start point
What is an advantage of systematic sampling?
It’s quick to use
What is a disadvantage of systematic sampling?
Sampling frame is required
What is stratified sampling?
Proportionally represents strata (groups) in the sample to reflect the population, use either simple random or systematic to fill the groups
What is an advantage of stratified sampling?
Reflects population
What is a disadvantage of stratified sampling?
Need clear strata for population
What are the types of non random sampling?
- opportunity sampling
- quota sampling
What is opportunity sampling?
Sample based on who/what is available
What is an advantage of opportunity sampling?
Easy and cheap
What is a disadvantage of opportunity sampling?
Unlikely to be representative
What is quota sampling?
Starts with quotas to be filled, but not necessarily representative of the population. Groups filled using opportunity sampling
What is an advantage of quota sampling?
No sampling frame needed
What is a disadvantage of quota sampling?
Not random, potential bias
What are the data types?
- qualitative
- quantitative
- discrete
- continuous
What is qualitative data?
non-numerical data
