Hypothetico-Deductive Model

The basic steps in Popper's model of scientific research can be identified as follows:

If you want to consider the above in more detail, the following provides an outline of each of Popper's stages in the development of a scientific research process…

1. Phenomena

This refers to anything in the world that catches our attention and which we want to describe, analyse and / or explain. It is the starting-point for all social research and, at its most basic, this idea simply refers to the fact that we are going to choose something to research. This first stage of the research process, therefore, is its most general and in order to actually do social research we have to narrow this down into something more specific.

A desire to research the area of "crime", "family life" or "education" might be examples here.

2. Observation and Generation of Ideas

This refers to this process of narrowing our research topic into something more specific and manageable. For example, as we take a closer interest in the topic of "crime" we start to look at things that do and don't interest us in this area. As we consider these things we start to generate possible ideas that we might like to investigate further. These can take the form of a "research question or problem".

Although more specific than the first stage we need, according to Popper, to be more specific still. This leads to the development of an hypothesis. For example, Why do people steal? Does the availability of divorce lead to family breakdown? etc.

3. Development of a Testable Hypothesis

An hypothesis can be defined as a general question or statement that suggests a possible (and therefore testable) relationship between two or more things.

For example, if we think about a research question such as

"Why do people steal?"

a major problem we have is how to answer such a question. It is too general for research purposes because it doesn't specify a relationship between "people" and "stealing" that can be tested. What we need to do, therefore, is to create an hypothesis (or series of related hypotheses) that turn our research problem into something we can test (by collecting and analysing evidence). Thus, we could create a testable hypothesis along the following lines:

"Poverty makes people steal".

Although this is a very simple (and probably not very useful) hypothesis, it does serve to illustrate the idea of the need to specify a testable relationship between two or more things. For example:

Thing 1 = Poverty

Thing 2 = People who steal.

The relationship in this instance is a casual one (that is, poverty somehow makes people steal. In effect,  "People who are poor will steal to feed their family").

From the above, it should be clear that the idea of developing a testable hypothesis is a useful step in the research process, mainly because an hypothesis provides both a focus for research and a clearly-defined objective for the data collection step (the researcher is going to collect data that will test the hypothesis).

Once a hypothesis has been developed, the researcher can move onto the next step in the process - the collection of data to test the hypothesis.

4. Systematic Observation and Data Collection

The next step in the research process, therefore, is the collection of data that allows the researcher to test their hypothesis. This is the stage at which various methods of research are introduced and since there are a wide variety of methods available we will need look at these separately - and in some detail - in further Units in this Module. However, two points can usefully be noted here:

Firstly, data collection must be systematic (planned and organised carefully to ensure that relevant data is separated from irrelevant data and so forth).Secondly, we need to understand that in order to test a hypothesis by collecting and analysing data we have to do two things: Firstly, we need to define the elements in the hypothesis carefully and unambiguously. Secondly, we have to develop some way of measuring each element in the hypothesis. In research terms this is called the operationalisation of a concept.

In basic terms, we operationalise a concept by developing indicators that we can measure. In sociology, many of the relationships you research involve concepts (ideas like "society", "norms" and "anomie") that can't be easily defined and measured because they don't physically exist. We need, therefore, to develop indicators of their existence that can be physically measured.

The idea of operationalizing a concept means the ability to transform a general, abstract, idea into something that can be defined and, most importantly, measured.

5. Data Analysis

Once data has been collected it has to be analysed (interpreted) in relation to the original hypothesis. This will involve things like:

* Checking to ensure that sufficient data has been collected.

* Checking that the sample used has remained representative.

* Making decisions about whether or not to include or discard data that appears irrelevant.

The outcome of this process is the next step.

6. Testing of Hypothesis

Once the data has been analysed a decision can then be made about whether or not the tested hypothesis has either been:

1. Shown to be untrue (falsified) or 2. Shown to be true (confirmed).

If the evidence collected suggests that the hypothesis is false (stage 7), a decision has to be made (stage 8) about whether it should be totally rejected or whether it can be revised and re-tested in a slightly different form (a return to stage 3).

If, on the other hand (stage 7b), the hypothesis is not shown to be false (for example, if all of the poor who were sampled and researched we involved in theft), hypothesis can be considered as confirmed and contributes to the final stage in the research process.

In everyday usage, a theory is normally taken to mean something that has not been tested. In sociological terms, however, this is considered to be incorrect because it confuses the concepts of hypothesis and theory.

A theory consists of an hypothesis (or, more usually, many related hypotheses) that has already been tested against the evidence and shown to be confirmed. In scientific terms, therefore, a theory consists of tested and confirmed hypotheses that can then be used to predict the behaviour that was originally observed (step 1).

7a. Hypothesis Falsified (Refuted)

If, on the basis of systematic observation and testing the hypothesis has been shown to be false, the next step is:

8a. Reject and / or Revise Hypothesis (return to step 3)

In other words, you need to either reject the hypothesis outright (and create a completely new testable hypothesis) or, more-likely perhaps, you need to revise the hypothesis in some way so that it can be retested in a slightly different form.

7b. Hypothesis is Confirmed

If the hypothesis could not, on the basis of available testing and evidence, be disproved, the researcher has the basis for the next stage in the model.

8b. Theory

A theory, in this interpretation, consists of confirmed hypotheses (since any any large-scale piece of social research it is highly unlikely that a researcher would be testing a single hypothesis. Once this stage has been reached it should, according to Popper, be possible to make predictions about behaviour based on the theory that has been developed.

9. Prediction

In logical terms, once the stage of "a theory" has been reached it is possible to make predictions based on that theory. While this is certainly true in the natural sciences (chemistry, physics and so forth), it is debatable as to whether or not a social scientist (a sociologist or psychologist, for example) would ever be able to reach this stage (for a variety of reasons that I don't propose to examine here).

Note: In everyday language "theory" and "hypothesis" are frequently confused. When people talk about "something working in theory but not in practice" what they are actually referring-to is an hypothesis rather than a theory.

Return