Critically Evaluating Quantitative Research Assignment

Critically Evaluating Quantitative Research - Assignment Example The use of the terms â€Å"quantitative† and â€Å"qualitative† in categorizing variables should not be mistaken with the use of these same terms to describe research approaches. The quantitative and qualitative variables described below both occur within quantitative research; qualitative research takes into account no such variables because it deals with explanation and interpretation of phenomena and do not categorize information in the form of variables (Hopkins, 2008; Hunter & Leahey, 2008; UNESCO, 2011). Quantitative or continuous variables may be classified as interval-scale, continuous ordinal, or ratio-scale. Interval-scale variables have order and equal intervals, are linear, and may assume positive or negative values. Continuous-ordinal variables may or may not be linear (i.e., it may be exponential, logarithmic or other monotonic transformation); they therefore lose their interval-scale property, and the observations are therefore best expressed by their ran ks which is the only certain parameter. Ratio-scale variables are continuous positive measurements on a nonlinear scale, such as the growth of bacterial population; in such a case, the population grows or multiplies at a ratio, for equal time intervals (UNESCO, 2011). Qualitative or discrete variables are also known as categorical values. ... The process of measurement may involve different procedures, depending upon the thing being measured (Gay, 1996). Variables in the physical sciences or areas of inquiry are usually measured according to a deterministic or positivist manner; this means that the measurements obtained are detectable and verifiable by the five senses, so they are more or less objective (Kincheloe, 1998; Colwell, 2006; Palmo, Weikel & Borsos, 2006; Hammersley & Atkinson, 2007) . On the other hand, measurements of variables that have a bearing in the social sciences are usually probabilistic in nature, which means that the actual measure may only be conjectured at with a certain degree of accuracy that is less than 100 per cent, and therefore prone to some subjectivity in the determination. An example of this is psychometrics, the field of study that measures the social and psychological attributes pertaining to certain phenomena (Rust & Golombok, 1999; Rao & Sinharay, 2007; Furr & Bacharach, 2008). Since the attributes measured are essentially internal processes that occur in the mind, they may be observed only from their external manifestations, or what are thought to be such, and from thence rendered into measurable quantities qualified by probability. Measurement is therefore indirect rather than direct (Kincheloe, 1998; Colwell, 2006). For directly observable things, measurement is straightforward, needing only physical counting or the use of such measuring tools as gauges, scales or meters. For those quantities that may not be directly measured, there are different approaches. One is the use of proxies (e.g. stand-ins); these are manifestations other than the variable being actually measured, that are