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Research Methods
What are experiments?
The experiment is the main method of the natural sciences. In an
experiment, the researcher identifies and controls all the variables
(factors) that might affect the outcome of the situation being
studied. By manipulating the variables – we can establish a cause and
effect relationship
There are three types of experiments:
•Laboratory experiment – takes place in an artificial setting e.g. A
lab and gives the researcher more control over the variables
•Field experiments – takes place in ‘real world’ situations (outside a
lab) and are more true to real life – but the researcher can’t control
all the variables
•Comparative method – carried out in the mind of the researcher
(‘thought experiment’)
Who do you think prefers these types of experiment and why?
Introduction:
Positivists favour the laboratory experiment as it achieves their main goal
of reliability:
•Careful control over the experimental conditions and variables allows for
more reliable data because other researchers can replicate the
experiment
•It allows the researcher to identify and measure behaviour patterns
quantitatively and manipulate variables to establish a cause-and-effect
relationship
However, control of all variables isn’t always possible or ethical and the
small sample size limits the extent to which generalisations can be made
Interpretivists reject the laboratory experiment because it fails to
achieve their main goal of validity. It is an artificial situation producing
unnatural behaviour. Interpretivists favour more naturalistic field
experiments, but positivists criticise this method for reducing control
over variables.
Laboratory experiments:
A laboratory experiment takes place in a controlled setting where
the researcher manipulates an independent variable (the cause) to
see if it changes the dependent variable (the effect). There are
usually two groups; the experimental group (which experiences the
IV) and the control group (which doesn’t experience the IV). All
other variables will be held the same for both conditions.
Reliability:
Consider the answers to the following
questions in pairs:
 What does this mean?
 Lab experiments are done under tightly
controlled conditions, do you think they are
reliable?
 What type of sociologists may like this
method?
 Lab experiments are done in an artificial
setting…Do you think lab experiments are
valid?
Advantages:
Advantages
•Because we can control all the variables / environment we can
be certain of cause-and-effect relationships e.g. whether
labelling affects pupils’ achievement – increasing the validity.
•Lab experiments have high reliability – this is because other
scientists can repeat a lab experiments in every detail as clear
standardised procedures are used and there are full control
over the variables.
•The laboratory experiment is a very detached method; the
researcher merely manipulates the variables and records the
results, objectivity is therefore high (the scientist’s personal
feelings and opinions have no effect on the outcome of the
experiment)
However, there are several reasons why experiments cause problems
– even for positivists!
Practical problems:
•Society is a complex phenomenon – therefore practically it
would be impossible to identify and control all the variables
that may exert an influence on, say, a child’s educational
achievement or worker’s attitude to work.
•Lab experiments cannot be used to study the past since it is
difficult to control all variables that were acting in the past
•Only study small samples. Very difficult to investigate large
scale social phenomena such as religions or voting patterns.
Small scale samples reduces their representativeness.
Free will:
•Interpretivists (interactionist) sociologists argue that human
beings are different from rocks, plants – humans have free
will, consciousness and choice
•This means our behaviour cannot be explained in terms of
cause and effect. It can only be understood in terms of the
choices we freely make.
•Therefore lab experiments are not an appropriate method to
study human beings.
Ethical problems:
Watch the following clip:
http://www.youtube.com/watch?v=W147ybOdgpE
What ethical problems do you think might arise from this lab
experiment?
Ethical problems:
•There are ethical (moral) objections to conducting experiments.
Experiments involve some kind of ‘blind’ to conceal the real aims of
research from the subjects (called deception), to avoid participants
changing their behaviour as a result.
•This means the participant cannot give their full informed consent –
if they don’t know what the true aims of the study are
•Lab experiments can create emotional and psychological distress for
the participant
RESEARCH:
Milgram (1974) study on obedience to authority. He lied to his participants
about the purpose of the research telling them they were assisting in a
learning experiment, in which they had to deliver electric shocks when the
learner got the answer incorrect. In reality there was no electric shocks and
Milgram was observing their willingness to obey orders. It was found 65%
delivered what they thought were highly dangerous electric shocks. This
caused a lot of psychological harm to his participants: “sweating, stuttering,
trembling”.
Supporters state that this was ethically justified to gather highly valid data.
The Hawthorne Effect:
A laboratory is not a natural experiment – therefore
participants’ behaviour may change as a result of being
observed/watched – if this happens then this will produce
invalid data
If they know they are being studied they may try to secondguess what the researcher wants they to do and act
accordingly. This would ruin the experiment – this is called the
Hawthorne effect.
Hawthorne Effect – Mayo (1927):
Elton Mayo conducted research into factors affecting workers’ productivity
at the Western Electric Company’s Hawthorne plant in Chicago.
Working with 5 female volunteers – Mayo altered variables like the lighting,
heating, breaks, etc. To see whether this affected their productivity. It was
found that their productivity improved when their working conditions
improved, but also surprisingly when conditions were worsened. Mayo
concluded that participants were not responding to the changes he was making
but simply due to the fact they were being observed and wanted to please the
experimenter.
Field experiments:
•Field experiments take place in the real social world (e.g.
School, workplace) – where sociologists either creates a
situation or adapts an existing real-life situation to their
research purpose.
•Those involved are usually unaware that an experiment is
taking place
•The aim of field experiments is to obtain some elements of
control while avoiding the artificiality of the laboratory.
Field experiments – Research support:
•Rosenhan (1973) is an example of a field experiment.
•Researchers presented themselves at 12 California mental
hospitals, saying they had been hearing voices. Each was
admitted and diagnosed with schizophrenia. Once in hospital
they stopped complaining of hearing voices and began to act
‘normal’. Nevertheless hospital staff treated them as though
they were mentally ill. The label of ‘schizophrenia’ led staff to
treat them differently.
Evaluation
 More ‘natural’, valid and realistic and avoid the artificiality
of lab experiments.
 However field experiments have less control over the
variables- cannot be certain that the causes we have
identified are the correct ones.
 Can be unethical since they involve carrying out the
experiment without pp’s consent.
Field experiments - Advantages:
•Less artificiality – set in real-world situation. Therefore
creating more valid data.
•Validity – because people are unaware of the experimental
situation and are in their usual social environment, they will
act normally. Their reactions will be genuine and the data
collected will high in validity.
•Those involved are not aware they are being studied –
reducing the Hawthorne Effect.
TASK - Read and make notes on the AO2 support
research by Rosenhan (1973):
This is an example of a field experiment – this shows the value of
field experiments. They are more ‘natural’ and realistic and avoid the
artificiality of lab experiments
Field experiments - Disadvantages:
•Less control over variables – field experiments do not meet
the rigorous scientific criteria of the lab experiment –
therefore we cannot be certain whether the causes we have
identified are correct or whether there were other external
factors that could have affected the results
•Limited application – there are few situations that can be
adapted to become a field experiment. They only measure
what people do, not why they do it.
•Ethical problems – they do not gain informed consent of
those involved because this would give the game away.
Comparative method:
This avoids the need to actually experiment on people (it’s a
‘thought experiment’), and does not involve the researcher
actually experimenting on real people at all. However, like lab
and filed experiments, it too is designed to discover cause-and
effect relationships. It works as follows:
• Step 1: Identify two groups of people that are alike in all
major respects except for one variable we are interested
in.
• Step 2: The compare the two groups to see if one
difference between them has any effects.
Durkheim (1897) comparative method:
Durkheim believed that Catholics had lower levels of suicide because
they were highly integrated into social groups compared to
Protestants (more individualistic). He tested his prediction by
comparing the official statistics of suicide rates of Catholics and
Protestants and found that Catholics had a lower level of suicide
rate.
Comparative Method - Advantages:
The comparative method has 3 advantages over lab
experiments:
•It avoids artificiality
•It can be used to study past events
•It poses no ethical problems, such as harming or deceiving
participants.
Comparative Method - Disadvantages:
•Even less control over variables – so we can be less certain
whether a thought experiment really has discovered the cause
of something – reducing the validity of the data.
TASK – Complete the questions on page 34