Define Internal and External Validity and Explain Five Threats to Internal

question 29

Essay

Define internal and external validity and explain five threats to internal validity and two threats to external validity.

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Definitions:

Posterior Probabilities

Posterior probabilities are the revised probabilities of events occurring after taking into consideration new evidence or information.

P(A ∪ B)

The probability that at least one of two events, A or B, occurs, including the possibility that both events occur simultaneously.

P(A | B)

Conditional Probability of A given B, representing the probability of event A occurring given that event B is known to occur.

Independent Events

Two or more events where the occurrence or outcome of one event does not affect the occurrence or outcome of the other event(s), a fundamental concept in probability.