External validity is about the generalizability of the results to different populations, settings, periods, treatment variables, and measurement variables. Then, threats to external validity are the conditions that limit this generalization of the results. Since external validity specifies conditions under…
We are very well aware of type I and type II errors in statistics. However, there is the error of the third kind or type III error that is more conceptual than type I and type II. It results from…
Empirical research is often conducted to establish evidence of a phenomenon or relationship, to examine and evaluate causal relationships, or to provide an explanation of how, why, and under what conditions a causal relationship exists. The purpose of the research…
In the previous post, we talked about measurement validity. But validity also relates to the ability of the research design to provide evidence of a cause-and-effect relationship between the independent and the dependent variable. This type of validity is known…
Validity in scientific research is arguably one of the most important properties of measurement as every aspect of research design can impact the validity of the research. Cook and Campbell (1979) defined it as “the best available approximation to the…
Consider if you were a photographer who has the perfect zoom lens and a great wide-angle lens. You can choose to photograph things in extreme detail or you can choose to photograph a big picture that provides a broader context.…
There are many types of variables in scientific research. Before we list out all and define them, let’s define the term variable itself. Paul Spector (1981) provides a succinct definition stating, “a variable is a qualitative or quantitative entity that…
“Science consists of some specific aims to arrive at a knowledge of some specific kind, methods for arriving at those aims together with the standards for judging the extent to which they have been met, and specific facts and theories…
Research, generally, has a specific goal. Scientists choose from different types of research available to fulfill their goals. A good starting point for understanding the various ways one could go about doing research is to get an understanding of research…
