Variable Whether we accept it or not, we all make value judgements constantly in our daily lives: ‘This food is excellent’; ‘I could not sleep well last night’; ‘I do not like this’; and ‘I think this is wonderful’. These are all judgements based upon our own preferences, indicators or assessment. Because these explain feelings or preferences, the basis on which they are made may vary markedly from person to person. There is no uniform yardstick with which to measure them. A particular food may be judged ‘excellent’ by one person but ‘awful’ by another, and something else could be wonderful to one person but ugly to another. When people express these feelings or preferences, they do so on the basis of certain criteria in their minds, or in relation to their expectations. If you were to question them, you will discover that their judgement is based upon indicators and/or expectations that lead them to conclude and express a particular opinion. Let us consider this in a professional context: ‘This programme is effective.’ ‘This programme is not effective.’ ‘We are providing a quality service to our clients.’ ‘This is a waste of time.’ ‘In this institution women are discriminated against.’ ‘There is no accountability in this office.’ ‘This product is not doing well.’ These are not preferences per se; these are judgements that require a sound basis on which to proclaim. For example, if you want to find out if a programme is effective, if a service is of quality or if there is discrimination, you need to be careful that such judgements have a rational and sound basis. This warrants the use of a measuring mechanism and it is in the process of measurement that knowledge about variables plays an important role. An image, perception or concept that is capable of measurement – hence capable of taking on different values – is called a variable. In other words, a concept that can be measured is called a variable. However, there are some who believe that scientific methods are incapable of measuring feelings, preferences, values and sentiments. In the author’s opinion most of these things can be measured, though there are situations where such feelings or judgements cannot be directly measured but can be measured indirectly through appropriate indicators. These feelings and judgements are based upon observable behaviors in real life, though the extent to which the behaviors reflect their judgements may vary from person to person.
The difference between a concept and a variable Measurability is the main difference between a concept and a variable. Concepts are mental images or perceptions and therefore their meanings vary markedly from individual to individual, whereas variables are measurable, though, of course, with varying degrees of accuracy. A concept cannot be measured whereas a variable can be subjected to measurement by crude/refined or subjective/objective units of measurement. Concepts are subjective impressions which, if measured as such would cause problems in comparing responses obtained from different respondents. It is therefore important for the concepts to be converted into variables (either directly or through a set of indicators) as they can be subjected to measurement, even though the degree of precision with which they can be measured markedly varies from one measurement scale to another (nominal, ordinal, interval and ratio). Converting concepts into variables If you are using a concept in your study, you need to consider its operationalization – that is, how it will be measured. In most cases, to operationalize a concept you first need to go through the process of identifying indicators – a set of criteria reflective of the concept – which can then be converted into variables. The choice of indicators for a concept might vary with the researcher but those selected must have a logical link with the concept. Some concepts, such as ‘rich’ (in terms of wealth), can easily be converted into indicators and then variables. For example, to decide objectively if a person is ‘rich’, one first needs to decide upon the indicators of wealth. Assume that we decide upon income and assets as the indicators. Income is also a variable since it can be measured in dollars; therefore, you do not need to convert this into a variable. Although the assets owned by an individual are indicators of his/her ‘richness’, they still belong to the category of concepts. You need to look further at the indicators of assets. For example, house, boat, car and investments are indicators of assets. Converting the value of each one into dollars will give the total value of the assets owned by a person. Next, fix a level, based upon available information on income distribution and an average level of assets owned by members of a community, which acts as the basis for classification. Then analyses the information on income and the total value of the assets to make a decision about whether the person should be classified as ‘rich’. The operationalization of other concepts, such as the ‘effectiveness’ or ‘impact’ of a programme, may prove more difficult. One of the main differences between quantitative and qualitative research studies is in the area of variables. In qualitative research, as it usually involves studying perceptions, beliefs, or feelings, you do not make any attempt to establish uniformity in them across
respondents and hence measurements and variables do not carry much significance. On the other hand, in quantitative studies, as the emphasis is on exploring commonalities in the study population, measurements and variables play an important role.