Amos Viviancos Leon 1
Chapter 1 thinking critically with psychological science
The need for psychological science: two phenomena- hindsight bias and judgmental overconfidence- illustrate why we
cannot solely rely on intuition and common sense. The critical inquiry that flows from a scientific approach- supported by
curiosity, scepticism, and humility- helps separate sense from nonsense.
A. Limits of intuition & common sense: Intelligence is a very inaccurate instrument
1. Hindsight bias (I-Knew-It-All-Along phenomenon): The tendency to believe, after learning an outcome, that one
would have foreseen it.
Finding out that something has happened makes it seem inevitable. E.g. “absence makes the heart grow fonder” and
“out of sight, out of mind” two sayings that mean the opposite, but when explained to different people they tend to
think that it is common sense.
2. Judgemental Overconfidence: Humans share a tendency to be overly confident. We tend to think that we know
more than we do. This contaminates our everyday judgement.
B. The scientific attitude: underlying science is a passion to explore, to understand without misleading, or being mislead.
In the scientific attitude, a prediction has to be confirmed. Someone with this attitude has to be sceptical, but open. He
has to have certain about on humility since they will have to reject their own ideas.
Critical thinking: thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions,
discerns hidden values, evaluates evidence, and assesses conclusions.
C. The scientific method: to make observation, form theories, and then refine their theories in the light of new
observation. P. 25 for diagram.
Theory: an explanation using an integrated set of principles that organizes and predicts observations.
Good theory organizes observed and observes facts; furthermore, implies predictions (hypothesis) that anyone can use to
check the theory.
Hypothesis: supposition made as a starting point for further investigation. A prediction.
A good theory must produce testable predictions, called hypothesis.
Operational definition: a statement of the procedures (operations) used to define research variables. For example,
human intelligence may be operationally defined as what n intelligence test measures.
Replication: repeating the essence of a research study, usually with different participants in different situations, to
see whether the basic finding extents to other participants and circumstances.
Description: the starting point for any science is observation and description.
A. The case study: an observation technique in which one person is studied in depth in the hope of revealing universal
Case studies are a good insight into a particular case which gives us answers in which we can incorporate into the world
around us. The disadvantages; however, is individual cases can be misleading. And individuals can be a typical.
Unrepresentative information can lead to mistaken judgements and false conclusions.
B. The Survey: a technique for ascertaining the self-reported attitudes or behaviours of people, usually by questioning a
representative, random sample of them. Amos Viviancos Leon 2
Problem- asking questions is tricky, and the answer may depend on your use of the words and choice of respondents.
Wording effect: even changes in the order of wording of questions can change the answers. E.G. people are more
approving of “aid to the needy” than of “welfare”
Random sampling: every single person has an equal chance at being selected.
False consensus effect: the tendency to overestimate the extent to which others share our beliefs and behaviours.
Population: all the cases in a group, from which samples may be drawn for study.
Random sample: every single person in the given population has an equal chance at being selected.
C. Naturalistic observation: observing and recording behaviour in naturally occurring situations without trying to
manipulate and control the situation. A disadvantage, similar to the case study and survey, is that it does not explain
behaviour instead it describes it.
Correlation: a measure of the extent to which two factors related together, and thus of well either factor predicts the other.
Coefficient correlation is the mathematical expression of the relationship, ranging from -1 to +1. We represent these
correlations in graphs called scatter plot, a graph cluster of dots each which represents the values of two variables (X, Y).
The slope of the points suggests the direction of the relationship between the two variables (+ or -). The amount of scatter
suggests the strength of the correlation. This helps us see relationships that the naked eye might miss.
A positive correlations means that the two variables either raise or fall together; a negative correlation means that one
variable rises while the other falls. Correlation only indicates a relationship, not a causation patter.
A. Correlation and causation: a thinking error is assuming that correlation proves causation. It DOES NOT! No matter
how strong the relationship. It only indicates the possibility of cause – effect relationship.
Illustration correlation: the perception of a relationship where non-exists.
B. Perceiving Order in Random Events: searching for patters in an attempt to make sense of the world. Patters or
sequences occur naturally in sets of random data, but we tend to interpret these patters as illusory correlations.
Experimentation: to discover cause – effect relationship by combining different variables and observing the outcome.
A. Exploring cause and effect: controlling other factors so that the required factors can be studied without influences.
Experiments: a research method in which an investigator manipulates one or more factors (independent variable) to
observe the effect on some behaviour or mental process (dependant variable). By random assignment of participants.
The experiment aims to co