Psychological Research and
Scientific Method
The application of scientific method in psychology
What is the goal of science?
• Psychological research has 4 key objectives:
 Description (finding out what happens).
 Understand how & why something happens
 Use the new information to predict what will happen
in a specific context.
 Control a phenomenon (where appropriate!)
Description
• Detailed unbiased observations are
usually the key link between the real
world & scientific abstract ideas.
Descriptions allow psychologists to be
clear about the nature of the subject
matter, which can lead to possible
explanations later.
Understanding.
• Once a description has been established
our understanding to explain how & why
needs developing. Psychologists will
develop their understanding by testing
theories systematically….to find out
what they cannot explain.
• Hypothesis from a theory (not vice
versa) thus the theory is supported!
Prediction
• After the description and explanation, a
prediction is made.
• Psychologists work toward testing
specific predictions.
• E.g. Lack of control is related to
workplace stress, therefore we might
predict those who have no/low control in
their jobs are more likely to suffer
from stress.
Control
• The aim of psychologists (all scientists
for that matter!) is to control a specific
phenomenon by manipulating several
factors that cause it (think...Operant
conditioning!)
• Prediction and control are specifically important for applied
psychologists who use their psychological knowledge to bring
about change/improvements.
Traditional views of science.
• Objectivity is the key
 This emerged in the 17th
century in response to
previous methods.
 Greek methods
employed by the likes of
Aristotle were the main
methods used up to this
point.
 They used mainly cosmic
knowledge & logical
reasoning.
 Science does not allow
individuals to make
specific claims about the
physical/social world
based upon their personal
views.
 The likes of Watson
(1913) attempted
objectivity through the
investigation of
observable behaviour only.
 However this view has
been argued ‘robustly’ by
those who feel this is too
restrictive
Modern views of science.
• Objectivity: Regarded as an important
feature of scientific investigations.
• Replicability: Findings need to be replicable
to avoid basing policy, practice on a ‘fluke’.
• Paradigms: A world wide view of general
theoretical view that is accepted buy the
majority. It determines how researchers
approach their work.
Objectivity
• Popper (1972) challenged the assumption
of total objectivity. He argued it is
impossible to achieve objectivity (total!)
as values,beliefs,expectations influence
ones observations.
• OBSERVE NOW!
HMM!
• What you observe is largely based upon
what you expect to see.
• In research this is driven by what we
hypothesise.
HMMM!!!
• Remember what
the eye sees
(sensation) is
different form
what the
individual
actually sees
(Perception)!!
Are there other views?
• Some psychologists who support the social
constructivist view believe that data can
never be wholly objective, but rather our
knowledge & understanding of the social world
is based upon social constructs.
• In short:
• Our interpretation of data is determined by
cultural, social and historical influences.
But what about qualitative
methods?
• Interviews, observations and the list
goes on…
• The researcher is more interested in
feelings and the understanding of
meaning of ones inner world as a source
of data.
• Objectivity is not viewed as necessarily
an indication of worth of their research.
Replicability
• Need to be able to validate each others
findings. One can have increased
confidence when findings have been
replicated.
• Replication is essential for 2 reasons:
Guards against scientific fraud.
It enables testing to ensure the
findings were not the result of a fluke.
Replication
• Controlled labs usually give rise to good
replicability so long as details of the
study have been carefully detailed.
• Internal validity is usually higher when
investigations have been carried out
time and again. The trade off is when
the investigation has been carried out
outside the lab (social experiments).
Q: Is this the same for
qualitative studies?
• A: No…this kind of investigation provide what
is known as a audit trail/decision trail.
• This enables them to trace back specific
claims made by the researcher back to the
original data to check if they are appropriate.
• The trail provides a detailed acct of the
thoughts and decisions made by the
investigator.
How do I achieve replicability?
A: Follow these steps
• Note exactly what has been done.
How the study was carried out
No. of Ps, (characteristics, sampling etc).
Where study was carried out.
Raw data- how was it collected and
analysed
= Replicability.
Replicability + Type I/Type II
errors.
• Type 1: Null Hypothesis is rejected
when it should not have been.
• (Error of optimism)
• Type 2 : Null is retained when it should
not have been. (Error of pessimism)
• A single study could fall under either of
the above, so, replication helps to guard
against these types of omissions.
So where do Paradigms fit in?
• Thomas Kuhn claimed science develops by shifting the
previous school of thought and replacing with another
• ‘ A shared set of assumptions about the subject matter
of a discipline & the methods appropriate to its study’.
There are 3 stages to this development
• Prescience-Range of views, no accepted paradigm.
• Normal science-Generally accepted paradigm.
• Revolutionary science-Paradigm shift a replacement
occurs.
Review of learning.
You should be able to/answer
1. List the four main goals of science
2. What is the traditional view of science
objectivity and how is it achieved
3. Explain why it is not possible for
scientists to achieve total objectivity
4. Why is replicability important, what is
needed to enable researchers to
replicate the work of others
5. Describe what is meant by a paradigm.