Class Notes (1,100,000)
CA (630,000)
McMaster (50,000)
PSYCH (6,000)
PSYCH 1X03 (1,000)
Joe Kim (1,000)

PSYCH 1X03 Lecture Notes - Social Desirability Bias, Central Tendency, Blind Experiment

Course Code
Joe Kim

This preview shows pages 1-3. to view the full 9 pages of the document.
Psychology Online Lecture 2/3: Research Methods
Bernard Ho
September 16, 2010
Basic Rules of Scientific Inquiry
o When presented with two otherwise equally valid explanations, scientists tend
to prefer the simper of the two
o However, if one explanation can better account for the known facts, then the
more comprehensive explanation is likely to be adopted
o The principle of parsimony is specifically applied to the situation of competing
explanations that do an equally good job of accounting for the known facts
Natural order
o As far as possible, we will attribute the same effects to the same causes
o We assume that a behaviour (smiling) is a reflection of the same underlying
mechanism in all people all over the world
o It is the same root mechanism (happiness) that produces smiles on lottery
winners and proud grandparents everywhere
o This principle is only to be applied in situations comparing the same effects
o The same causes that produce our effects in the lab also produce those effects in
everyday life situations over which the scientist has no control
o Scientists are conservative in the sense that they tend to support the current
theory until new facts accumulate to force the theory to be modified or
Empiricism and Objectivity
o Modern scientific methodology is based on empirical data following the view
that knowledge should be based on actual observation and not on reason alone
o Not to say that logic and reason have no place in modern science, they play key
o We certainly cannot carefully observe everything, we must pick and choose
where to direct limited resources
Experience and common sense vs. scientific inquiry
o One of the main dangers of common sense is the phenomenon known as
hindsight bias
o When we learn something new, we have a tendency to think that we could have
guessed it, or we already partially knew it
o It is this bias that can allow any reasonable statement to be categorized as
common sense
o Any explanation makes sense and seems like common sense to us, even when
the information is new or not intuitive

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Scientific Method
1. Construct a theory
a. General set of ideas about the way the world works
b. Begin by studying the existing collection of information about the world, such as
previous work published by other scientists
c. Operation definition
i. Describes the actions or operations that will be made to measure or
control a variable in any given study or experiment
ii. Without such an operation definition, it would be possible to consider a
wide range of behaviours to be indicative of any terms under different
2. Generate a hypothesis
a. Testable statements guided by theories that make specific predictions about the
relationship between variables
3. Choose research method
a. The way in which a hypothesis will be tested
b. Methods such as experiments allow scientists to collect data about how the
events of the world unfold, which may or may not be in line with their
c. Scientists analyze the data to note any specific trends or relationships that the
research has revealed, ultimately leading to the decision to accept or reject the
original hypothesis
4. Collect data
a. Taking measurements of the outcome of the test using one or more of several
5. Analyze data
a. Understand the data and discover trends and relationships between variables
b. Ultimately leading to the decision to accept or reject the hypothesis
6. Report findings
a. Publish articles in scholarly journals
b. Individual scientists and scientific community as a whole review all findings on a
topic to revise existing theories that define our current understanding of the
c. Undergoes a rigorous referee process to ensure research is scholarly, accurate
and meaningful to the field
7. Revise existing theories
a. To include new information into our understanding of the world
b. Paradigm shift
i. Particularly dramatic change in our way of thinking
Provides a standardized process for scientific research
Minimizes biases, conflicts and other problems to promote accurate results and
scientific discourse

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Conducting an Experiment (hypothesis)
Eric sees an infomercial for “MegaStudy”, which enhances memory and helps focus
during studying
Test performance can be affected by external factors
Students taking energy drink should show higher test scores compared to
those not taking the drink
Anecdotal evidence
Evidence gathered from others or self experience
If he gets good grade drink worked
If he fails drink fails
Problems with testing a hypothesis
Single experience may not be representative of the general result
that would occur if it was repeated several times
Can't be sure your experience is the same as what others would
experience under the same circumstances
Can’t be sure that any change in test performance was due to the
drink at all (easier/harder test, studied more etc.)
Control Groups
Experiment (choosing research method)
Scientific tool used to measure the effect of one variable on another
A variable is anything that is free to take on different values
Scientist manipulates independent variable and observes the effect the
manipulation has on the dependent variable
Eric has not properly manipulated the independent variable
Control groups
Eric will take a test after drinking the energy drink, but he will ask his
roommate to take the same test without taking the drink
However, what if Eric is smarter than his roommate?
In simplest form, contains two groups
Experimental group
o Receive manipulation of independent variable during the experiment
Control group
o Does not receive manipulation
Participants in both group should be as similar as possible
o Eric might try to find a student who gets the same mark as him, but
also who studies similar to him and takes the same classes
Within-subject design
Tests the same subject repeatedly while the independent variable is
You're Reading a Preview

Unlock to view full version