Statistics and Mechanics Chapter 1 - Data Collection Flashcards
Flashcards covering all information needed from Chapter 1 of the Statistics and Mechanics ActiveLearn textbook.
Quota sampling
The population is split into groups and a certain number from each group is chosen in any order.
Stratified sampling
The population is split into groups and a proportional representation of the different groups is selected.
Simple random sampling
Every member of the population has an equal chance of being selected.
Opportunity sampling
A convenient sample is taken from any members of the population at any time.
Systematic sampling
A repetitive system used to select a sample from the population.
A researcher uses simple random sampling on a list of gym members to research what times they go to the gym. What is the sampling frame?
The membership list.
Pros and cons of quota sampling
Pros:
No sampling frame required, allows a small sample to still be representative of the population, quick, easy, inexpensive
Cons:
Potential for bias, population must be divided into groups, which can be costly or inaccurate.
Pros and cons of stratified sampling
Pros:
Accurate, cost effective, prevents bias, guarantees proportional representation
Cons:
A sampling frame is needed, population must be clearly classified into distinct strata
Pros and cons of simple random sampling
Pros:
Simple, quick, cheap, free of bias, each sampling unit has an equal chance of selection
Cons:
Time consuming and expensive when sample size is large, requires a sampling frame
Pros and cons of opportunity sampling
Pros:
Quick and easy, does not need a sampling frame, inexpensive
Cons:
Unlikely to provide a representative sample, highly dependent on individual researcher
Pros and cons of systematic sampling
Pros:
Simple and quick, suitable for large samples
Cons:
Needs a sampling frame
What is a population?
The whole set of items that are of interest
Pros and cons of a census
Pros:
Should give a completely accurate result
Cons:
Time consuming, expensive, hard to process large quantity of data
Pros and cons of a sample
Pros:
Less time consuming and expensive than a census, less data than a census
Cons:
Data may not be as accurate, the sample may not be large enough to give information about small sub-groups of the population
What are sampling units?
The individual units of a population.
What is a sampling frame?
When sampling units are individually named or numbered.
What is quantitative data?
Variables or data associated with numerical obervations.
What is qualitative data?
Variables or data associated with non-numerical observations.
What is a continuous variable?
A variable that can take any value in a given range.
What is a discrete variable?
A variable that can take only specific values in a given range.