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This 10-minute tutorial describes four examples of how a Randomizer form can be used to carry out common research tasks such as drawing a random sample of individuals from a population.

To begin, simply scroll down to Lesson 1 below.

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Random Sample of 50 Students from a Population of 643

Survey researchers often use random sampling to measure public opinion because it's much cheaper to survey a representative sample of the public than to survey everyone. With the form below, it's easy to generate a random sample.

Let's say you're interested in studying student attitudes toward climate change. If you wanted to randomly sample 50 students out of 643 at a local school, you would need to number all 643 students (Student 001, 002, 003, etc.) and then use the Randomizer form to generate 1 set of 50 unique numbers with a range from 1 to 643.

These settings have been chosen in the Randomizer form below. Click the "Randomize Now!" button to get your results.


In some cases, you may wish to generate more than one set of numbers at a time (e.g., when randomly assigning people to experimental conditions in a "blocked" research design). If you wish to generate multiple sets of random numbers, simply enter the number of sets you want, and Research Randomizer will display all sets in the results.


Specify how many numbers you want Research Randomizer to generate in each set. For example, a request for 5 numbers might yield the following set of random numbers: 2, 17, 23, 42, 50.


Specify the lowest and highest value of the numbers you want to generate. For example, a range of 1 up to 50 would only generate random numbers between 1 and 50 (e.g., 2, 17, 23, 42, 50). Enter the lowest number you want in the "From" field and the highest number you want in the "To" field.


Selecting "Yes" means that any particular number will appear only once in a given set (e.g., 2, 17, 23, 42, 50). Selecting "No" means that numbers may repeat within a given set (e.g., 2, 17, 17, 42, 50).
Please note: Numbers will remain unique only within a single set, not across multiple sets. If you request multiple sets, any particular number in Set 1 may still show up again in Set 2.


Sorting your numbers can be helpful if you are performing random sampling, but it is not desirable if you are performing random assignment. To learn more about the difference between random sampling and random assignment, please see the Research Randomizer Quick Tutorial.


Place Markers let you know where in the sequence a particular random number falls (by marking it with a small number immediately to the left).

With Place Markers Off, your results will look something like this:
Set #1: 2, 17, 23, 42, 50
Set #2: 5, 3, 42, 18, 20
This is the default layout Research Randomizer uses.

With Place Markers Within, your results will look something like this:
Set #1: p1=2, p2=17, p3=23, p4=42, p5=50
Set #2: p1=5, p2=3, p3=42, p4=18, p5=20
This layout allows you to know instantly that the number 23 is the third number in Set #1, whereas the number 18 is the fourth number in Set #2. Notice that with this option, the Place Markers begin again at p1 in each set.

With Place Markers Across, your results will look something like this:
Set #1: p1=2, p2=17, p3=23, p4=42, p5=50
Set #2: p6=5, p7=3, p8=42, p9=18, p10=20
This layout allows you to know that 23 is the third number in the sequence, and 18 is the ninth number over both sets. As discussed in the Quick Tutorial, this option is especially helpful for doing random assignment by blocks.