1. Can a researcher prove conclusively that a study has internal validity? Explain
No. it is impossible to prove conclusively that a study has internal validity. This is because there are many threats to internal validity and it is sometime difficult to control all of them, especially the loss of subjects.
2. In chapter 6, we discussed the concept of external validity. In what ways, if any, are internal and external validity related? Can a study have internal validity but not external validity? If so, what about the reverse
External and internal validity are related because they both influence the validity of the research findings. Yes, a study may have internal validity and not external validity but not the reverse. It is impossible for the study to have external validity and lack internal validity.
3. Students often confuse the concept of internal validity with the idea of instrument validity. How would you explain the difference between the two?
Internal validity refers to appropriateness, correctness, meaningfulness, or usefulness of inferences drawn on a given research using by use of appropriate data. Instrument …show more content…
2). Maturation (natural development) threat to internal validity occurs when subjects change due to passage of time as opposed to specific events. 3). Testing effect causes a threat to internal validity due to changes on the measuring instruments. 4). Instrumentation error is a threat to internal validity due instability or variations in the measuring instruments. These may include such as changes in calibration of the instrument. 5). Statistical regression threat may occur when research participants selected by relying on extreme indicators and assessments exhibit unforeseen extreme outcomes. 6). Selection of subject’s threat occurs where research subject’s exhibit varied