standard_description: Recognize the purposes of and differences among sample surveys, experiments, and observational studies; explain how randomization relates to each.
problem_activity: Problem 1
Part A: Predict the shape of the graph at 2,000 trials.
|                                       10 trials                                        |                                       100 trials                                        |                                       533 trials                                        |
|----------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------|
| .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2018/06/05/algiiu8_l7_at1.png | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2018/06/05/algiiu8_l7_at1a.png | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2018/06/05/algiiu8_l7_at1b.png |
Part B: At 1,799 trials, the graph looks like this:
[IMG]
The mean of the data is approximately 6, and the standard deviation is 1.7. The blue lines around the graph are what should be the "ideal" normal distribution.
Describe what the mean and the standard deviation mean in terms of this situation.
Problem 2
Match the following distributions with the histograms. Explain your reasoning.
| **           Distribution          ** |                 **           Shape          **                 | **           Mean          ** | **           Standard Deviation          ** |
|---------------------------------------|----------------------------------------------------------------|-------------------------------|---------------------------------------------|
|      **           A          **       |          **           Skewed to the right          **          | **           100          **  |         **           10          **         |
|      **           B          **       | **           Approximately symmetric, mound shaped          ** | **           100          **  |         **           10          **         |
|      **           C          **       | **           Approximately symmetric, mound shaped          ** | **           100          **  |         **           40          **         |
|      **           D          **       |          **           Skewed to the right          **          | **           100          **  |         **           40          **         |
[IMG]


aligns: no