the difference between reliability and validity

An important consideration is that equivalency reliability is concerned with correlational, not causal, relationships.įor example, a researcher studying university English students happened to notice that when some students were studying for finals, their holiday shopping began. In quantitative studies and particularly in experimental studies, a correlation coefficient, statistically referred to as r, is used to show the strength of the correlation between a dependent variable (the subject under study), and one or more independent variables, which are manipulated to determine effects on the dependent variable. Equivalency reliability is determined by relating two sets of test scores to one another to highlight the degree of relationship or association. For researchers, four key types of reliability are: Equivalency ReliabilityĮquivalency reliability is the extent to which two items measure identical concepts at an identical level of difficulty. Reliability is such an important concept that it has been defined in terms of its application to a wide range of activities. In addition to its important role in research, reliability is critical for many parts of our lives, including manufacturing, medicine, and sports. Without the agreement of independent observers able to replicate research procedures, or the ability to use research tools and procedures that yield consistent measurements, researchers would be unable to satisfactorily draw conclusions, formulate theories, or make claims about the generalizability of their research. Reliability is the extent to which an experiment, test, or any measuring procedure yields the same result on repeated trials. These related research issues ask us to consider whether we are studying what we think we are studying and whether the measures we use are consistent.

The difference between reliability and validity