Please watch this on youtube: https://www.youtube.com/watch?v=TDCYJ3_gx2w

Answer the folloring:

In this video the author discussed several small investigations. Select one investigation discussed by the author, and reflect on the following questions:

1. Whether the author discussed observational studies or experiments

2. What variables were involved, which of them were categorical (ordinal, nominal), which were quantitative (interval, ratio).

3. If the author discussed observational studies, say what can be done to change them to experiments.

4. What were observational units?

5. What was the response variable?

6. If the studies were experiments, state the factor(s).

7. What main lesson did you learn from this video?