What is Experimental Psychology?

experimental psychology

We see many psychological studies being performed by different research organizations to prove or disprove hypotheses, as well as to understand different phenomena. To accurately and confidently arrive at a conclusion, researchers often employ different scientific methods. This is the main focus area of Experimental Psychology.

What is Experimental Psychology?

It is generally, the work that is being done by researchers who wish to study behaviors, as well as the different processes and functions that support these behaviors. Tests are performed either on test subjects to understand and learn about different topics, among which include perception, memory, sensation, learning, motivation and emotions.

The Four Canons of Science

To better understand the approach to experimental psychology, there are four fundamental principles that researchers generally agree on, for psychological studies to be deemed reliable:

Determinism
Studies look into events and focus on how they are affected by other events. It looks at the causality between two (or more ideas).

Empiricism
This idea believes that knowledge is only derived primarily from experiences that are related to the senses – only things that are observable can be studied.

Parsimony
This idea says that researches are to be done on the most simple of theories. If we are faced with two different, contrasting theories – the more parsimonious or basic theory is to be preferred.

Testability
This idea believes that hypotheses and theories should be testable over time.

Dependent and Independent Variables

Because experimental psychology is employed to identify the relationship between two factors, it is important to first identify the dependent and independent variables.

  • A dependent variable is usually the outcome or the effect.
  • An independent variable, on the other hand, is the influencing factor to the dependent variable.

For example, a study is being performed to test the relationship between emotions and memory. The hypothesis is that happier people remember better compared to those in a less positive mood. In this study, the emotions will be the independent variable, while memory is the dependent variable.

Operational Definitions

The operational definition is a way to define abstract ideas to make it observable and measurable. Going back to the study between emotions and memory, which are two very abstract ideas, researchers will need to provide operational definitions to measure the happiness of a person, as well as the strength of his or her memory. As an example, researchers can define happiness through a survey that is filled out by participants to gauge their current state; memory, on the other hand, can be tested by asking participants to recall the order of photos that will be shown to them later on.

Validity and Reliability

Validity is defined as the correctness and relative accuracy of the psychological studies. There are four types:

  • Internal validity, in which the study provides strong evidence to the causality between two factors. A study that has high internal validity arrives at a conclusion that it is indeed the independent variable that affects the independent variable.
  • External validity, in which the study can be replicated across different populations and still yield the same results.
  • Construct validity, in which the independent and dependent variables are found to be accurate representations of the abstract concepts that are being studied.
  • Conceptual validity, in which the hypothesis that was being tested supports the broader theory that is also being studied.

Reliability, on the other hand is defined as the repeatability and testability of a study. If the research can be repeated and still yield the same results (either on a different set of participants or during a different time period), then it is considered reliable.

What does an experimental psychologist do?

An experimental psychologist is usually found in universities, businesses, and even the government to conduct studies on related to factors mentioned above, among others. Apart from psychological processes, they also look into other ideas such as leadership, trust, and personality. Among the many experimental psychologists include Wilhelm Wundt, Charles Bell, and Ernst Heinrich Weber, the last of which is credited as one of the founders of experimental psychology.

Photo credit: Tim Sheerman-Chase

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