Distinguish between a population and a sample and investigate techniques for collecting data, including census, sampling and observation (VCMSP297)
LO: To investigate different techniques for collecting data.
Know:
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What the definition of census is and what is the advantage over sampling.
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What the definition of sampling is and what is the advantage over census.
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What the definition observation is.
Understand:
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That there are different ways of collecting data, each with their positives and negatives.
Do:
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I can use different survey techniques to collect data.
Elaborations
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identifying situations where data can be collected by census and those where a sample is appropriate
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investigating the differences between convenience, judgemental and simple random sampling from a population
Visual Representations
Teaching Notes
There are 2 general techniques for collecting data, Census and Sampling.
Census – a census is when you collect data for every member of the group from the data set.
Sampling (sample) – a sample is when you collect data for a selected members of the group.
Positives and Negatives
|
|
Positives |
Negatives |
Census |
+ More accurate because you have to survey everyone |
– Takes a lot of time to survey everyone |
Sampling |
+ Much quicker to survey a select few rather than the whole population |
– Less accurate as the sample might not be representative of the whole. |
Sampling (sample) – a sample is when you collect data for a selected members of the group.
Positives and Negatives
Teaching Ideas
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explain the relationship between a census, a representative sample, sample size, and a population (e.g.,“I think that in most cases a larger sample size will be more representative of the entire population.”
Collecting Data Videos
Practise Questions
Year 8 Big Ideas
Exercise 9A pg. 313 Now Try These: Q. 1-3
My Maths 8
Exercise 9A pg. 459 Q. 1-15