After a day off for election day, it’s back to the world of random sampling, margin of error and plausible intervals. These tend to be tricky ideas for students, as we move from the “absolute” world of algebra and into the slightly more wishy-washy world of sampling and plausability. My board scribblings were intended to remind students that we draw samples to represent populations, and that random sampling is king!
But random sampling is messy business, and there are other sampling techniques I want students to consider, and think about their effectiveness. Rather than lecture each type (caution – excessive vocabulary lectures may cause drowsiness), I gave students a list of words I expected them to research and find suitable resources.
- Cluster Sampling
- Stratified Sampling
- Systematic Sampling
- Convenience Sampling
After a few rounds of walking around the room to discourage random copying of definitions which they didn’t understand anyway, many groups began to ask the “right” questions, relating the ideas to hypothetical surveys we could do of high school students. Towards the end of our time, each group was assigned one term to “explain” on a poster through a visual representation. And now, we have a great crowd-sourced wall of survey vocabulary to refer to during discussions!
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