People rely on folk psychology (intuition and common sense)
Pseudoscience: statements, beliefs, or practices that claim to be scientific or factful but are not linked to scientific method
Biases
Hindsight bias
"I-knew-it-all" phenomenon, the tendency to believe, after learning about an outcome, that we foreseen it
Overconfidence bias
The tendency for a person to overestimate their abilities
Order in random events
Given random data, people look for order, for meaningful patterns
Observer bias
An error due to the personal motives and expectations of viewer
(can be minimized by operational definition)
Techniques that eliminate bias
Double-blind control
Purpose of experimentation
Purpose: to find out whether changes in one variable(X) cause changes in another variable(Y)
X: Independent variable, researcher changes
eg. stimulus or cause
Y: Dependent variable, the one being observed
eg. response or effect
Investigators assemple 2 groups of subjects who are treated differently with regard to the independent variable
<font color="#2196f3">Extraneous variable</font>: other variables other than independent variable, might influence the dependent variable
<font color="#2196f3">Confounding variable</font>: 2 variables link in a way that makes it difficult to sort out their specific effects
Experimental group: consists of the subjects who receive special treatment in regard to the independent variable
Effects
Unintentional expectancy effect
a researcher subtly communicates to the research participants the behaviors he or she expects to find, thereby producing desired reaction
Placebo effect
when experimental participants change their behavior in the absence of any kind of experimental manipulation
Experimenters must be aware that participants change the way they behave simply because they are aware of being observed or tested
Sampling
Representative sampling
a subset of a population that closely matches the overall characteristics of the populations
Random sampling
every member of a population has an equal likelihood of participating in the experiment
Note: sampling bias exists when a sample is not representative of the population from which it was drawn
Descriptive method
Descriptive method permits investigators to see only whether there is a link or association between variables of interest
