1) What is the difference between random selection and random assignment? How are they related to internal and external validity? 2

1) What is the difference between random selection and random assignment? How are they related to internal and external validity?

2. Random selection is using a chance procedure to draw a sample from a population. Because it addresses the question of how well results drawn from a sample can be generalized to the population from which the sample was drawn, it is a strategy for increasing external validity. Random assignment is using a chance procedure to assign the subjects available for an experiment to treatment. It is a strategy for increasing internal validity