Post on 18-May-2015
11.2 Collecting and Displaying Data
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11.2 Collecting & Displaying Data
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Definitions
Population: All the individual in the group being studied.
Example the population in a federal election is all eligible voters
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Definitions
Sample: Any group of individuals selected from the population.
Example: A sample of the population in a federal election might be 100 individuals chosen from each province.
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SampleRandom
Sample
Convenience Sample
Stratified
Sample
Systematic
Sample
Voluntary Response Sample
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Definitions
Convenience Sample: A sample created by choosing individuals from the population who are easy to access.
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Definitions
Random Sample: A sample created by choosing a specific number of individuals randomly from the whole population.
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Definitions
Stratified Sample: A sample created by dividing the whole population into distinct groups, and then choosing the same fraction of members from each group.
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Definitions
Systematic Sample: A sample created by choosing individuals at fixed intervals from an ordered list of the whole population.
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Definitions
Voluntary Response Sample: A sample created by inviting the whole population to participate.
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ExampleIdentify whether you would use the entire population or just a sample.
1. Electing the Prime Minister of Canada
2. Selecting music for a school dance
3. Checking if fireworks are working before a show
4. A family deciding where to go for supper
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ExampleWhat type of sample is the following? Do
the results accurately reflect the population.
A teacher wishes to get feedback from her class about the school dance. She plans to survey 5 students out of a class of 30 by putting all the students' names in a hat and drawing 5 names.
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ExampleWhat type of sample is the following? Do
the results accurately reflect the population.
A marketing research company mails surveys to all of the adult residents in a town. The survey asks about brands of consumer products. The residents are asked to mail their responses in a prepaid envelope.
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ExampleWhat type of sample is the following? Do
the results accurately reflect the population.
A restaurant owner wants to know the favourite pizza topping of his customers. He plans to survey every customer who orders a pizza in his restaurant between 5:00 pm and 10:00 pm one evening.
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ExampleWhat type of sample is the following? Do
the results accurately reflect the population.
A chain store is trying to decide whether to open a store in Camrose, Alberta. The company decides to survey people in Camrose and three nearby towns. The population is shown in the table. The company decides to survey 25% of the population.
Location Population
Camrose 16 000
Bashaw 825
Tofield 1 876
Daysland 876
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Displaying Data
Bar Graph
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Displaying Data
Circle Graph
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Displaying Data
Line Graph
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