What Makes a Good Sample? - 7th data & statistics

Last updated over 2 years ago
10 questions
The price per pound of catfish at a fish market was recorded for 100 weeks.

Here are dot plots showing the population and three different samples from that population.
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What do you notice?
What do you wonder?

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If the goal is to have the sample represent the population, which of the samples would work best?

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If the goal is to have the sample represent the population, which of the samples wouldn't work very well?

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What are some aspects that makes for a good sample?

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What are some aspects that makes for a BAD sample?

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If you were to find a measure of center to represent a typical value for the population above, would you use mean or median? Explain

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When doing a statistical study, it is important to keep the goal of the study in mind.

Representative samples give us the best information about the distribution of the population as a whole, but sometimes a representative sample won't work for the goal of a study!

For example, suppose you want to study how discrimination affects people in your town. Surveying a representative sample of people in your town would give information about how the population generally feels, but might miss some smaller groups.

Describe a way you might choose a sample of people to address this question.

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What does it mean for a sample to be representative of the population?

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Why might it be important to get a representative sample rather than a more convenient sample?

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Usually, a sample is used because we can’t get data for the entire population.

How do we know if the sample is representative of the population if we don’t know the population?