Use the Following to Answer Questions

Multiple Choice

Use the following to answer questions
Scenario I
A psychologist interested in studying visual perception manipulates the brightness of a light in the imperceptible to very dim range.Each level of brightness (measured in lumens) is studied for 10 trials,and on each trial participants are asked if they can detect the light.Figure 4.1 shows hypothetical data from one participant.
Figure 4.1
-(Scenario I) Suppose two people differ in terms of their absolute threshold for light but this difference is extremely small (1 lumen) .Because the projection device can only manipulate lumens in steps of 5,the researcher concludes that the absolute threshold for the two participants is equivalent.In this case,the measure lacks:

A) reliability.
B) statistical significance.
C) power.
D) validity.