Using Studies Wisely (Lesson 4.8)
Chapter 4 - Day 10
Identify the population to which inferences from a sample can be made.
Determine when it is appropriate to make an inference about cause and effect.
Evaluate if a statistical study has been carried out in an ethical manner.
Before starting the activity, you may want to remind students of the purpose of taking a random sample and using random assignment with the following two images from earlier in the course:
A random sample should be representative of the population, so we can generalize our conclusions from the sample to the population.
We use random assignment in an experiment to create two groups that are roughly equivalent, so that if there is a difference in the response variable at the end of the experiment, we can say the treatment caused the change.
This lesson uses a card sort, where students match 6 different conclusions to 6 different study designs. Here are three options for how you can have students do the card sort:
Cut out the conclusions before class. Put all 6 in a single envelope. Have students write out the conclusions on their activity sheet as they match them up.
Have students cut out the 6 conclusions. They can then tape/paste them onto the activity.
Have students do the card sort digitally using this Desmos activity.
To start the debrief, ask the whole class a few questions:
What clues were given in the study design that helped you figure out the first part of the conclusion (the group of students we can generalize to)?
What clues were given in the study design that helped you figure out the second part of the conclusion (association or causation)?
Hopefully students realize that we need to know whether or not there is a random sample to determine the group to generalize to and whether or not there was random assignment to determine if we can claim causation.
In the end, we showed students this table as a summary of the lesson: