the application of scientific method in psychology

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THE APPLICATION OF SCIENTIFIC METHOD IN PSYCHOLOGY

To read up on the application of scientific method in psychology, refer to pages 687–699 of Eysenck’s A2

Level Psychology.

Ask yourself

What is the scientific method?

Is psychology a science?

 What is peer review?

What you need to know

THE NATURE OF

“SCIENCE”

NON-SCIENTIFIC

APPROACHES TO

PSYCHOLOGY

THE SCIENTIFIC

PROCESS

THE ROLE OF PEER

REVIEW IN

VALIDATING

KNOWLEDGE

Key features of science

The scientific method, including theory constructio n, hypothesis testing, use of empirical methods, generation of laws/princi ples (e.g.

Popper and

Kuhn)

Humanistic approaches

Social constructionis t approaches

 The steps in the scientific process

 The peer review

 process

Criticisms of

 the process

The importance of the process in validating knowledge

THE NATURE OF “SCIENCE”

There is reasonable agreement that the following are key features of science:

1.

Controlled observations: in most sciences it is typical for experiments to involve observing the effects of some specific manipulation, e.g. mixing two chemicals together. As applied to psychology, this generally involves observing the effects of some manipulation of the environment on participants’ behaviour. Thus, the experimental method has the great advantage over other methods in that it allows us to have some confidence that the independent variable has influenced the dependent variable, and so cause and effect can be established.

2.

Objectivity: even if total objectivity (free from bias) is impossible, it is still important for data to be collected in a way as close to objectivity as possible.

It is impossible to carry out research that is completely objective as Popper

(1969, 1972, see A2 Level Psychology page 688) demonstrated in a now

famous lecture, which involved him telling the audience, “Observe!” The obvious and immediate retort was, “Observe what?”, which makes the point that no one ever observes without some idea of what they are looking for.

Thus, scientific observation is always driven by what you expect to see and so cannot be free from bias.

3.

Testing theoretical predictions: scientific experiments are generally carried out to test the predictions of a theory. Theoretical predictions need to be tested because science advances when inadequate theories are replaced by ones that are more consistent with the data.

4.

Falsifiability: the notion that scientific theories can potentially be disproved by evidence. Popper (1969, see A2 Level Psychology page 690) argued that the hallmark of science is falsifiability and this is what distinguishes science from religions and pseudo-sciences such as psychoanalysis and Marxism.

Scientists should form theories and hypotheses that can, potentially, be shown to be untrue by experimental tests. In scientific research a null hypothesis is stated; this predicts no difference between the conditions or an association between two variables. It is the null hypothesis that is actually the starting point and it is this that you are setting out to test, not the alternative hypothesis. Research mainly seeks to reject the null hypothesis although some research does seek to show no difference. Research that tests a hypothesis that can be rejected if not supported by the research findings is said to be falsifiable. However, there are a number of psychological theories that do not have a testable hypothesis because the concepts cannot be measured, and so they cannot be falsified, e.g. evolutionary and psychoanalytical theories.

5.

Replicability: the findings obtained by researchers need to be replicable or repeatable; it would be hard (or impossible) to base a science on inconsistent findings. Replicability of findings in psychology varies enormously as a function of the area of psychology under investigation and the type of study being performed. Replicability tends to be greatest when experiments are conducted in a carefully controlled way, and it tends to be lowest when the experimenter is unable to manipulate the variable or variables of interest.

Thus, laboratory experiments permit a high degree of replicability, but are not without weaknesses. The fact they are replicable is because they are conducted in a controlled environment, but this also means they are artificial and so may not be generalisable to other settings, and therefore lack external validity.

6.

Paradigm: there is a generally accepted theoretical orientation or paradigm within a science. Thomas Kuhn (1962, 1970, 1977, see A2 Level Psychology page 693) argues that a paradigm is the most essential ingredient in a science.

Kuhn (1962, see A2 Level Psychology page 694) argued that psychology has failed to develop a paradigm and so remains at the pre-science stage. The fact that there are several general theoretical approaches within psychology (e.g. psychodynamic, behaviourist, humanist, cognitive) supports the fact that there is no one agreed paradigm. Also, psychology is an unusually fragmented discipline. It has connections with several other disciplines, including biology, physiology, biochemistry, neurology, and sociology. For example, psychologists studying biochemistry have very little in common with those studying social factors within

society. The fragmentation and diversity make it unlikely that agreement can be reached on a common paradigm or general theoretical orientation. This might not make psychology any less scientific than the other sciences, although this is often assumed to be the case. Kuhn’s view of traditional science using the same paradigm exaggerates the similarity of perspective found among researchers in physics, chemistry, biology, and so on.

NON-SCIENTIFIC APPROACHES TO PSYCHOLOGY

Some approaches to psychology place much less emphasis on the notion of psychology as a science.

Humanistic psychologists and social constructionists agreed strongly that psychology should not be a science, and social constructionists went further and argued that it cannot be a science. The humanistic psychologists (e.g. Maslow, Rogers, see A2 Level Psychology page 695) were opposed to the traditional scientific approach to psychology because they favoured the use of phenomenology, in which individuals report their conscious experiences in as pure and undistorted a way as possible. Such reports meet one of the major aims of science understanding, but they do not meet two of the other aims, prediction and control.

Psychologists who favour social constructionism argue that there are no objective data and that our

“knowledge” of ourselves and of the world is based on social constructions. They argue research cannot be objective because the observations made by psychologists, and the ways those observations are interpreted, are determined to a large extent by the cultural and historical forces influencing them.

Although there is some validity in the social constructionist position, many psychologists regard it as making exaggerated claims. For example, suppose several people saw a police officer hitting a student hard with a long stick. Regardless of their beliefs, they would probably be able to agree on the basic facts of what had happened. However, there would be much disagreement as to whether the police officer’s action was justified or unjustified. In other words, our beliefs can colour our interpretation of an action, but they are less likely to influence our description of that action.

THE SCIENTIFIC PROCESS

The scientific process takes a particular form. It begins with:

 Observation of subject matter

This leads to the:

 Formulation of theory

The next step is to test the theory:

 Hypotheses construction

Hypotheses are tested through research:

 Empirical methods

New knowledge cannot be accepted uncritically, it must be checked:

 Replication and validation of new knowledge through peer reviews

THE ROLE OF PEER REVIEW IN VALIDATING KNOWLEDGE

Peer review refers to the process by which peers evaluate a researcher’s work before it appears formally in print. It is a means of assessing the quality of psychological research. The work of specialists is submitted to a qualified adjudicator—an editor—who in turn sends it to fellow specialists—referees—to seek their advice about whether the paper is potentially publishable and, if so, what further work is required to make it acceptable. The paper is not published until and unless the recommended revision can be and is done to the satisfaction of the editor and referees.

An issue with peer review is that it can be biased. Referees may be biased if they favour a different approach or the editors can be biased in their use of the feedback provided by the referees because they can misinterpret or misapply referees’ advice. The internet offers the potential to improve on this because it speeds up the process and so more referees can be used, thereby reducing any selectivity in the feedback.

So what does this mean?

It is hard to decide whether psychology should be regarded as a science. In general terms, psychology possesses many of the features of a science. Thus, there are good reasons for arguing that psychology is on the way to becoming a science. At present, however, it should probably be regarded as having only some of the features of a science rather than being a fully-fledged science.

Over to you

1.

Outline the key features of science. (6 marks)

2.

Explain the role of peer review in validating knowledge. (4 marks)

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