An understanding of basic statistics will provide you with the fundamental skills necessary to read and evaluate most results sections. Examples of the itemised rating scale are illustrated in figure 3. If the scale items were adequately developed and scored, the economy and effectiveness of data reduction present in the Bogardus social distance scale would appear. Semantic Differential Scale Max Diff A is a combination of more than one continuum. Using either procedure one can, for example, ascertain the degree to which two or more survey respondents agree in their ranking of a set of items. This process is referred to as measurement.
But if we asked students after the first week about their confidence of being able to pass the course, that might be considered a quantifiable qualitative matter, or do I have my terminology completely wrong? A ratio scale is the top level of measurement and is not often available in social research. Scales of Measurement in a nutshell refers to various measures of the variables researchers use in their research, variables in the research are fall in one of 4 scales of measurement that will be discussed in this article. Likert scale is an example of ordinal scale. The factor which clearly defines a ratio scale is that it has a true zero point. An example of the use of an ordinal scale would be a study that examines the smoking rates of teenagers. Presumably, if a person is willing to accept a certain association, he is willing to accept all those that precede it on the list those with lesser intensities , though this is not necessarily the case as some critics of this scale point out.
Say, for example, we wanted to know the level of job satisfaction nurses experience working on various units within a particular hospital e. This characteristic of classification if fundamental to all scales of measurement. For example, in the study cited above, is the difference in recorded absenteeism between psychiatric and obstetrics nurses large enough to conclude that there is meaningful difference in absenteeism between the two units? This process continues until all possible combinations are exhausted, in this case 10 pairs. The data could be arranged in order and examined in terms of the number of smokers at each level. However, it is an important topic since the type of scale used in taking measurements directly impinges on the statistical techniques which can legitimately be used in the analysis. We can conceive of an absolute zero of length and similarly we can conceive of an absolute zero of time.
. Identify what you are trying to measure. In addition, it involves the ranking of variables. Given that sociological and management research seldom aspires beyond the interval level of measurement, it is not proposed that particular attention be given to this level of analysis. One common use of the Likert scale is a survey that asks respondents to offer their opinion on something by stating the level to which they agree or disagree.
Quantitative Scales of Measurement This module discusses the basics of measurement and scales of measurement commonly used in quantitative research. The resultant coefficient takes a value in the range 0 to 1. Again, it does not make sense to add together first and second place in a race--one does not get third place. Your questionnaire would look something like this:. What are the major statistical limitations to nominal scaled data? On the theory of scales of measurement.
In these cases, the distances are note equal but they are strictly definable based on the metric used. Example variables could be levels of depression or anxiety or the level of physical functioning of a patient. These constitute a hierarchy where the lowest scale of measurement, nominal, has far fewer mathematical properties than those further up this hierarchy of scales. Examples of variables which are ratio scaled include weights, lengths and times. Qualitative outcomes might be if someone feels their economic situation has improved, and if they think it's due to the project.
Measurement scales while framing a questionnaire play an important role to understand the characteristics of the variables. Nominal scale is the least powerful level of measurement. When you are asked to rate your satisfaction with a piece of software on a 7 point scale, from Dissatisfied to Satisfied, you are using an interval scale. If numerals are assigned to ordinal scale categories, the numerals serve only as ranks for ordering observations from least to most in terms of the characteristic measured and they do not indicate the distance between scale that organizes observations in terms of categories such as high, medium and low or strongly agree, agree, not sure, disagree, and strong disagree. That determines statistical operations we can use.
Interval and Ratio data are sometimes referred to as parametric and Nominal and Ordinal data are referred to as nonparametric. If you are 20 years old, you not only know that you are older than someone who is 15 years old magnitude but you also know that you are five years older equal intervals. A discussed the important points to remember while making a questionnaire. In essence, respondents are ranking the items in order of the weakest indicator of discrimination all the way to the strongest indicator. On the Theory of Scales of Measurement. It is best to use an existing instrument, one that has been developed and tested numerous times, such as can be found in the.