About this video
A census collects data on every member of the population you care about. Inspecting every bench in Rivermeade Park is a census of that park's benches, but checking every cart at only one of a grocery chain's five stores is not a census of the chain's carts.
You'll be able to
- define a census as collecting data on every member of a population.
- identify the population in a data collection scenario.
- decide whether a data collection method is a census.
Key words
- census
- Collecting data from every member of the population, not just some.
- population
- The whole group you want to learn about.
Transcript
- [Instructor] A city's parks department wants to know the condition of the benches in Rivermeade Park. A crew inspects every bench in the park and records whether it needs repair. Is this data collection method a census? So pause this video and have a go at this before we do it together.
Okay, so let's just remind ourselves what a census is. That's where you're collecting data on every member of a population. So here the population are the benches in Rivermeade Park and they say a crew inspects every bench, not just some of the benches, not just most of the benches, every bench.
So that's what makes it a census. Yes, because the crew recorded information from every bench in this park. Yep, I like that. See, yes, because the crew inspected a large number of benches. Nope, that would not make it a census. It has to be every. No, the parks department did not inspect benches in the city's other parks.
That would be the case if it was a census of all of the city's parks. But we're assuming here this is a census of the benches in Rivermeade Park. They want to know the conditions of the benches in Rivermeade. They're not saying a city's park wants to know the condition of all of the benches in the city and then they're just inspecting every bench in Rivermeade.
Then yes, then C would actually be the case, if they wanted a census on the whole city. No, because the crew recorded a condition for each bench rather than counting the benches. No, you're not counting the benches, you're recording condition, so I like choice A.
Let's do another one. So here, we're told a grocery chain wants to know how many of the shopping carts at its five stores have a broken wheel. An employee checks every cart at the Oak Street store and records whether its wheels are working. Is this data collection method a census?
Again, pause and figure it out. All right, so what they want to know is how many of the shopping carts at its five stores have a broken wheel. So if you really wanted to do a census, you would have to look at every shopping cart at all five stores. What they tell us is that the employee checks every cart at only one of the stores, only at the Oak Street store.
So this is definitely not a census. They would have to do it all five, if they wanted a census across the five stores. So let's see. No, because the carts at the chain's other stores were not checked. Yep, that is exactly what we are talking about.
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