An experimenter is planning to do a random groups design experiment to study the effect of the rate of presenting stimuli on people’s ability to recognize the stimuli. The independent variable is the presentation rate, and it will be manipulated at four levels: Very Fast, Fast, Slow, and Very Slow. The experimenter is seeking your help and advice with the following aspects of the experiment:

A. The experimenter asks you to prepare a block randomized schedule such that there will be four participants in each of the four conditions.

To do this, you can use the following random numbers that were taken from the random number table in the Appendix (Table a.1).

B. The experimenter is considering restricting participants to those who pass a stringent reaction time test so as to be sure that they will be able to perform the task successfully with the Very Fast presentation rate. Explain what factors the experimenter should consider in making this decision, being sure to describe clearly what risks, if any, are taken if only this restricted set of participants is tested.

C. The experimenter discovers that it will be necessary to test participants in two different rooms. How should the experimenter arrange the testing of the conditions in these two rooms so as to avoid possible confounding by this extraneous variable?

Table a.1

Transcribed Image Text:

1-5-6-6-4-1-0-4-9-3-2-0-4-9-2-3-8-3-9-1 9-1-1-3-2-2-1-9-9-9-5-9-5-1-6-8-1-6-5-2 2-7-1-9-5-4-8-2-2-3-4-6-7-5-1-2-2-9-2-3