Sampling Flashcards
(25 cards)
What is qualitative data?
Non-numerical values.
What is quantitative data
Numerical values.
What is quota sampling?
The population is divided into groups based on a characteristic A quota is then set in each group.
What are advantages of quota sampling?
- small sample is still representative
- quick, easy, cheap
- allows for easy comparison.
- no sampling frame required
What are disadvantages of quota sampling?
- Non-responses aren’t recorded
- non-random sampling can introduce bias
- Population must be divided into groups.
What is opportunistic sampling?
A sample taken from people who are available at the time and meet the criteria.
What are advantages of opportunistic sampling?
- easy to carry out
- inexpensive
What I disadvantages of opportunistic sampling?
- Unlikely to provide a representative sample
- highly dependent on individual researcher.
What is a census?
Measuring every member of the population.
What are advantages of a census?
Completely accurate results.
What I disadvantages of a census?
- Expensive
- time consuming
- hard to process large quantities of data
- destroys the item
What is a sample?
Measuring a part of a population.
What are advantages of a sample?
- Less time consuming
- cheaper
- fewer people have to respond.
What are disadvantages of a sample?
- May be too small
- data may be inaccurate.
What is simple random sampling?
Every sample has an equal chance of being selected.
What are advantages of simple random sampling?
- Free of bias
- easy and cheap for small populations.
What are disadvantages of simple random sampling?
- Not suitable for large populations
- sampling frame needed.
What is systematic sampling?
The elements are chosen at regular intervals from an ordered list.
What are advantages of systematic sampling?
- Quick and simple
- suitable for a large populations.
What are disadvantages of systematic sampling?
- Sampling frame needed
- could introduce bias if not random.
What is stratified sampling?
The proportion of each strata is the same.
Were advantages of stratified sampling?
- accurate
- proportional to the population size.
What are disadvantages of stratified sampling?
- Population must be in distinct stratas
- sampling frame needed.
If the relative humidity is above 95%, what would the weather be like?
Misty and foggy conditions.
