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A good way to understand random sampling, random assignment, and the difference between the two is to draw a random sample of your own and carry out an example of random assignment. To complete this assignment, begin by opening a second web browser window (or printing this page), and then finish each part in the order below.

Part I: Research Randomizer Tutorial
The first part of this assignment is to complete a 10-minute web tutorial on random sampling and random assignment. To complete the tutorial:
- Visit Research Randomizer.
- Read the introductory page and check that you have an adequate web browser as described under System Requirements (if not, either update your browser or use a different computer).
- Once you know that your browser is adequate, click on the Tutorial button near the top of the Research Randomizer screen.
- Go through all four examples in the tutorial.
Tip: After you click on the "Randomize Now!" button to generate numbers in a tutorial lesson, examine the results closely before advancing to the next lesson.

Part II: Random Sampling
Suppose you have a numbered list of 3,000 students at your school, and you want to draw a random sample of 100 students for a study you're conducting. In the old days this would have been a time consuming task, but with Research Randomizer, you can generate the results in less than a minute. Here's what you need to do:
- Click on Randomize near the top of the Research Randomizer screen.
- Fill in the Randomizer form with the appropriate values.
Tip: There's no need to sort the numbers, because you'll be calling students in the random order that their number appears in your sample.
- Click the "Randomize Now!" button to get your results.
- Print out the results to be handed in at the beginning of class next time.

Part III: Random Assignment
Suppose you contact the 100 students from Part II to participate in a laboratory study with five conditions, 50 students agree to participate, and you renumber these students from 1 to 50. In this last part of the assignment, your task is to assign each participant to one of five conditions. Here, for example, is what the end result might look like:
Block 1:
Participant 001: Condition 2
Participant 002: Condition 1
Participant 003: Condition 5
Participant 004: Condition 3
Participant 005: Condition 4
Block 2:
Participant 006: Condition 3
Participant 007: Condition 2
Participant 008: Condition 4
Participant 009: Condition 1
Participant 010: Condition 5
And so on...
To complete this step, just generate 10 sets of random numbers ranging from 1 to 5 so that within each block of five students, one person is randomly assigned to each different condition. Here's how:
- Close the first results window and return to the Randomizer form.
- Change the Randomizer values as needed.
Tip: Blocked designs are covered in Lesson 3 of the tutorial in Part I above.
- Click the "Randomize Now!" button to get your new results.
- Print out the results to be handed in at the beginning of class next time.
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