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Suppose that you would like to know if keyboard design has an effect on wrist angle, as shown in the accompanying figure. You have 40 volunteers who have agreed to participate in an experiment to compare two different keyboards. Describe a method for randomly assigning each of the volunteers to one of the experimental groups.

Short Answer

Expert verified
Random assignment can be done by assigning a unique number to each volunteer and then using a Random Number Generator to select 20 volunteers for the first group. The remaining ones are assigned to the second group. This ensures fair and unbiased group formation.

Step by step solution

01

Grasp the Concept of Random Assignment

Random assignment is a procedure in conducting experiments in which the participants have the same chance to be assigned to any given group. This is usually carried out to ensure that each participant has an equal opportunity to be placed in any group and to minimize bias in the distribution of participants.
02

Understand the Task

In this case, there are two different keyboard designs to test, and you have 40 volunteers. So, two experimental groups are needed. Each group should ideally contain 20 volunteers.
03

Describe the Random Selection Procedure

Start by giving each volunteer a unique identification number from 1 to 40. Then, use a Random Number Generator to generate 20 different and unique numbers from 1 to 40. The volunteers corresponding to these 20 numbers will form the first group and the remaining 20 will be in the second group, ensuring fair and unbiased group formation.

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