A firm wants to evaluate a leadership program. Upper-level managers are asked to evaluate the leadership of their mid-level managers and then pair up managers having about the same levels. One member of each pair is assigned to the program which consists of extreme physical exertion such as mountain climbing. Although only half of those selected completed the program, one year later those mangers completing the program were compared on leadership ability to their matched pairs who had not taken the program. It was found that those completing the program were rated higher than their matched pairs. What threat to internal validity might be operating here?
A) selection
B) history
C) mortality
D) statistical regression
Question 2
Suppose you wish to compare computer-aided instruction with traditional lectures. One year the course is presented traditionally and the next using computers. You discover that the students in the computerized course do better on the final exam but you also discover that admission standards at the school were tightened in the second year. You have a problem with ____ as a threat to internal validity.
A) testing
B) selection
C) history
D) maturation
Normal development of posture and spinal curves. (A) Toddler: Protruding abdomen; lumbar lordosis. (
Muscles of the right upper extremity back view
Injecting the upper outer quadrant of the buttocks.
The Upper Troposphere: Troughs and Ridges
How to evaluate algebraic terms containing fractional exponents without a calculator (Part 2)
The quaternary level of protein structure as seen in hemoglobin