Ch 3 - The validity of measurement

             Defining and measuring variables in the scientific research process is a crucial step to secure that the study is successful and obtain the expected results. To understand how the variables can be affected and interfere with results under different conditions is necessary that they can be measured.

              The variables that are essential to predict a given behavior can be represented as a hypothetical construct. Trough operational definition, researches may define and measure how this construct will be evaluated, like loneliness,  for example. Understand how an intangible variable can be observed and studied, depend on the quality of which operational definition will be used to be sure that it will measure what is proposed to be.

              Validity is one of the essential criteria to evaluate a measurement procedure. Despite the  obvious concept, this criteria confers reliability about what has being measured, specially if the object of measurement is a hypothetical construct and cannot be assessed in another way. However, trough previous consulting of much previous research is possible to acknowledge ideas about conventional methods of defining and measuring variables that could be applied to your scientific study as well.