High quality quantitative dissertations are able to clearly bring together theory, constructs and variables. Broadly speaking, constructs are the building blocks of theories, helping to explain how and why certain phenomena behave the way that they do. During the dissertation process you will need to clearly and precisely explain the theories, constructs, and variables that you are interested in, as well as explain the relationship between them. In this article, we focus on constructs. We explain (a) what constructs are, (b) the use of theoretical or nominal definitions to express the meaning of constructs, and (c) the need to create operational definition from constructs so that they can be measured. Each of these aspects of constructs is discussed in turn:
Constructs are mental abstractions that we used to express the ideas, people, organisations, events and/or objects/things that we are interested in. Constructs are a way of bringing theory down to earth, helping to explain the different components of theories, as well as measure/observe their behaviour. The table below provides some examples of these different types of constructs:
| Types of constructs | Examples |
| Ideas | Ageism, sexism, racism, self-esteem, poverty, social capital, trust, philanthropy, affluence, morality, tolerance, air pollution, genetic engineering, euthanasia, marriage, taboos |
| People | Age, gender, ethnicity, height, obesity, morbidity, energy, muscle soreness, fatigue |
| Organisations | Financial performance, corporate social responsibility, firm survival, organisational culture, service quality, corporate governance, outsourcing, alliances |
| Events | Armageddon, famine, urban regeneration, Jihad, secularism |
| Objects/Things | Sun, hurricanes, tsunamis, trees, flowers, amino acids, stem cells |
The examples above highlight a desire to capture what we mean about something through the use of just a few words (often only one or two words). Take the following examples:
| The meaning we are trying to convey | Construct |
| Prejudice or discrimination on the grounds of a person's age | Ageism |
| The problem of obesity - the state of being grossly fat or overweight - among children | Child obesity |
| The formal union of a man and a woman, typically recognized by law, by which they become husband and wife | Marriage |
| Extreme scarcity of food | Famine |
| The painless killing of a patient suffering from an incurable and painful disease or in an irreversible coma | Euthanasia |
| A long, high sea wave caused by an earthquake or other disturbance | Tsunami |
NOTE: Definitions are verbatim from Oxford Dictionaries (www.oxforddictionaries.com), a great online resource.
We often refer to constructs as mental abstractions because seldom are constructs directly observable (e.g., we cannot directly observe depression, even though we may associate depression with signs such as a person that often cries, engages in self-harm, has mood swings, and so forth). Since constructs are very broad and abstract, conceptual clarity has become one of the cornerstones of good research.
Constructs vary significantly in their complexity. By complexity, we mean the relative difficulty that people have understanding and measuring (i.e., observing) various constructs. Some constructs can be very easy to understand/measure (e.g., age, gender, ethnicity, height), but others are more difficult/complex (e.g., ageism, sexism, racism, self-esteem). Take the following examples:
Easy to understand and measure:
We know that the construct, sex, has just two attributes in humans: male and female. If we choose to include the construct, sex, in our research, this would be relatively easy to justify. After all, most people would associate the construct, sex, as referring to males or females.
More difficult to understand and measure:
Some constructs that we think we understand, and that we think the reader will understand, can be more complex than we first thought. For example, take gender. You often see students include the construct, gender, in questionnaires, giving respondents just two options (i.e., male and female). This is because the constructs of sex and gender are often used interchangeably. But social scientists would argue that gender is a more complex construct, including additional attributes to just male and female; perhaps including bisexual, homosexual, transsexual, and so forth. In reality, a significant proportion of constructs are of the more complex type.
This difference in complexity raises two issues: (1) the need to explain to the reader what you mean when you use a particular construct; and (2) the fact that a construct can have more than one meaning, highlighting the importance of explaining what the construct means to you.
Constructs provide a common language and shared meaning that help us to communicate about things clearly and precisely. Imagine a discussion about marriage, having to continuously explain terms such as divorce, civil partnerships, love, sex, intimacy, religion, sanctity, cohabitation, engagement, and so forth. Imagine a debate about famine, without knowing the meaning of other constructs such as starvation, drought, poverty, disaster relief, food supply, survival, nutrition, aid, and so forth. Without a clear and precise way of explaining what these constructs mean, we would struggle to communicate to our audience.
Constructs often lack clarity and precision; they are ambiguous. Sometimes in undergraduate and master?s level dissertations, they are even unstated. However, constructs need to be expressed (i.e., made explicit) in a way that is clear, precise, and non-ambiguous, so that they can be shared (i.e., researchers, but also participants, must have a common understanding; that is, ?speak the same language?, but also reach the same meaning). Also, constructs need to be made explicit so that they can (a) be criticised, (b) related to other constructs, (c) operationally defined, and (d) tested (i.e., they are measurable).
As a result, theoretical or nominal definitions are used to provide conceptual clarity, using synonyms to express the construct we are interested in. These theoretical or nominal definitions can be found (a) in academic journals (usually the Abstract/Introduction/Literature Review; often early on); (b) in subject specific or standard dictionaries; or (c) created specifically where none exist. Constructs can be expressed using words (e.g., marriage, depression, hurricanes) or symbolic notations (e.g., % to denote percentages, µ to denote the mean). Constructs are also often defined in terms of other constructs (e.g., the construct, famine, which can be defined as "extreme scarcity of food", has been defined in terms of two other constructs, scarcity and food). However, some constructs (e.g., colours, smells, sounds) are more difficult to explain in this way; instead needing to be explained through direct experiences/sense. Some example theoretical and nominal definitions are presented in the table below:
| Construct | Theoretical or nominal definitions |
| Ageism | "A process of systematic stereotyping of and discrimination against people because they are old, just as racism and sexism accomplish this for skin colour and gender" (Butler, 1975, p.35). |
| Euthanasia | "The painless killing of a patient suffering from an incurable and painful disease or in an irreversible coma" (Oxford Dictionaries, 2011). |
| Social capital | "The sum of the actual and potential resources embedded within, available through, and derived from the network of relationships possessed by an individual or social unit" (Nahapiet & Ghoshal, 1998, p.243). |
Clarity is also required when setting out the constructs you intend to study because (a) the meaning/understanding that people get from a construct can be different, and (b) constructs can be viewed from a number of different perspectives, even when there is agreement of the meaning of constructs (e.g., intelligence may be viewed in terms of IQ, but also EI - emotional intelligence - or another perspective).
| Construct | Perspectives/approaches towards the construct |
| Disability | Perspective 1: Bio-medical approach Views disability as a medical or physical condition that can be prevented or reduced through interventions that are biological, medical or genetic in nature. Perspective 2: Functional approach Disability is viewed again as an individual condition, but focus is placed on ways to treat the functional incapacity this creates. Perspective 3: Rights-outcome approach Views disability as a consequence of the way in which society is organised, and the relationship between society and the individual. |
NOTE: Perspectives/approaches to disability from Rioux (1997).
Constructs can also have a number of different dimensions (e.g., the construct, organisational commitment, is often viewed as consisting of three dimensions - affective commitment, continuance commitment and normative commitment - which whilst constructs in their own right, are part of the broader construct, organisational commitment).
Ultimately, we have to make a choice between possible (i.e., multiple) theoretical or nominal definitions of constructs; we have to settle on a particular definition, but explain: (a) why we made this choice over definitions that adopt the same/similar approach, in terms of (i) how it fits with your research agenda and (ii) support for a definition in the literature amongst other researchers; and (b) how the conceptual definitions relates to other constructs, whether (i) in the same area or (ii) another conceptual area we are interested in. It is important to note that despite the need to make choices between conceptual definitions, there are no right or wrong answers.
Since a conceptual definition only provides the platform for the operational definition that is used to empirically measure constructs, we discuss about translating constructs into operational definitions in the next section.
Whilst constructs are sometimes mistaken for variables, they are not variables. Instead, we use variables to operationalize (i.e., measure) the constructs we are interested in. Constructs can be mistaken for variables because some constructs may only be represented by one variable, such that the construct name and the variable name are the same (e.g., the construct and variable, sex).
Therefore, constructs need to be translated from the abstract (i.e., mental ideas; mental abstractions) to the concrete (i.e., measureable/testable in the form of variables). In other words, we are re-stating constructs as variables, with variables also having their own attributes (e.g., gender having the attributes male/female, which is important, because gender is a classic example of where constructs/variables, and their attributes, can be confused). The role of the operational definition is to precisely describe how to measure the characteristics of a construct. By characteristics, we mean the mental abstractions/ideas within constructs that ultimately are measureable in the form of variables and their attributes. It is these variables and their attributes that are measured.
Constructs can be represented by a wide range of variables. For example, happiness could be associated with love, financial security, cigarettes, puppies, a song, ice cream, and so on. Translating abstract concepts (e.g., happiness) into concrete variables is not straightforward. People view constructs in different ways (e.g., in the case of happiness, people often adopt a perspective that focuses on actions, such as smoking a cigarette, or possessions, such as owning a diamond, so you need to be clear how you intend to operationalize a construct, and why you are making such choices).
Translating constructs into operational definitions can be an iterative process, but testing (i.e., the measurement process) should not start until a conceptual and operational definition of your construct(s) have been selected (i.e., you cannot have good measurement without conceptual/operational clarity of constructs).
Ultimately, the operational definition is seldom perfect; that is, the choice of operational definition may be constrained by factors such as a lack of access to operational/measurement data. Also, how we construct/formulate an operational definition will impact on the complexity of the measurement process.
In order to establish an operational definition of a construct, you also need to know about different types of variables [see the article: Types of variables].
Butler, R. N. (1975). Why Survive? Being Old in America. San Francisco: Harper & Row.
Nahapiet, J., & Ghoshal, S. (1998). Social capital, intellectual capital, and the organizational advantage. Academy of Management Review, 23(2): 242-266.
Oxford Dictionaries (2011). Dictionary: www.oxforddictionaries.com
Rioux, M. H. (1997). When myths masquerade as science. In L. Barton & M. Oliver. Disability Studies: Past, Present and Future. Leeds: The Disability Press.