STA630

STA630 Assignment # 1 Solution :

In this scenario,following threats to internal validity exist:

History effects

In the scenario above , Pakistan television programme was the history effect which was an external even out of control of management.All the employees take much interest in that programme due to which the validty of the training influence adversely.

Maturation effect

In the scenarion above , the length of time was too much according to some employees .And 3 employees left the training due to the fact that they were getting bored from training programme..Thats why this threat to internal validity exist in scenario.

Testing effect

This effect also exist in this scenario ,As the questions asked in pretest influence the performance of employees adversely.

Instrumentation effect

This is another threat to internal validity which exist in this scenario.The question asked in pretest were quite easy than the questions asked in posttest.Which influence the result of training program adversely.

Mortality

Mortality effect of threat to the internal validity exist I this scenari , as some of the employees left organization during programme .Which contaminate the programme because leaving of some members hinder the training process and make it difficult to intreprete the exact result.Following threats to internal validity does not exist in the scenario above.

Selection bias effect

This is the threat which exist due to non random selection of subjects for 2 comparison groups.Whereas in scenario above members of 2 groups were selected randomly.So, there was no selection differentiation in scenario.