Sampling
Describe how a simple random sample might be taken.
Assign a random number to each member of the population then use a random number generator/pick numbers form a hat to select the sample.
What is a census?
Research that is conducted on the entire population of interest.
What is meant by causation?
A relationship where changes in one variable are the direct cause of changes in another variable.
Sketch the graph of y = -x2 - 1
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You send out a survey to collect information for your research. What kind of sample are you collecting by doing this?
Self-selected.
What is a sample?
A group of elements from the population of interest that has been chosen to represent the population.
What is meant by correlation?
An observed association/connection between two variables.
Sketch the graph of y = |x+1| - 3
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What is a quota sample?
A sample in which you target a specific characteristic of the population and collect data until you have collected a specific number (quota).
What is a parameter?
A piece of numerical data about the population.
What is meant by a biased question?
A question which encourages the respondent to lean towards a specific response.
Sketch the graph of y = (x+1)3 + 5.
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What is a stratified sample?
A sample which proportionally represents certain features of the population.
What is a survey?
Research that is conducted on a sample.
What is meant by a biased sample?
A sample that does not fairly represent the population of interest.
Sketch the solution of:
y > (x-2)2
y < |x|
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How is a cluster sample collected?
The population of interest is divided into groups (clusters) then a number of these whole groups are randomly selected to create the sample.
What is a statistic?
Numerical data collected from a sample.
What is an observational study?
A study which does not impose any kind of change on the sample that is being studied.
Sketch the solution of:
y < (x-2)2
y > |x|
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