IPS - Day 33

Today was a short day due to state testing. The focus today was to solidify students' understanding of different sampling techniques.

To start things off we looked at the results of systematic sampling. The distribution was highly concentrated with all mean areas falling between 6 and 8 square units. At the same time, the center of the distribution was still very close to 7 square units, which was consistent with the other sampling techniques and which was the point.

I then had students create a table listing the various sampling techniques we have looked at: simple random sample (SRS), stratified sample, cluster sample, systematic sample, and multi-stage sample. I asked students to think about advantages, disadvantages, and questions they had for each.

This exercise really helped students to differentiate between the sampling techniques. Students started to better grasp what made cluster sampling different from stratified sampling. When discussing a SRS, students considered the idea that you could end up with a sample that might miss a key group, while a cluster sample may be overly generalizing a population's characteristics.

Because of the shortened class period this was all we were able to accomplish today. We'll take a look at bias next class. This is a natural extension as students mentioned bias as a possible disadvantage several times.

Visit the class summary for a student's perspective and to view the lesson slide.