Quantitative methods in psychology are those that deal with quantitative data; in other words they deal with numbers and statistics. The most common form of quantitative research is the experimental method.

All the topics of study in this unit will help you build the skills and knowledge that are needed for you to complete the Internal Assessment, where you get to carry out your own Psychology Experiment.

In the first introductory unit you will learn about laboratory experiments, but as we progress through the course you will learn about other quantitative methods, such as quasi experiments, meta-analyses and correlational studies. Through the study of these methods and examples of their use in real research studies it is hoped that you will develop an understanding of how and why various research methods are used to study behaviour.

It is also important that you develop the ability to think critically about the research you read. This means not believing every conclusion researchers present but critiquing the validity of these conclusions.

What you need to know…

By the end of this introductory unit on experimental research methods it is hoped that you will be able to answer the following questions. Both assessments *are designed to test your knowledge and understanding in these areas.

  1. What is the purpose of conducting an experiment?
  2. How is the aim of an experiment stated?
  3. What are independent, dependent and confounding variables?
  4. What is an “operational definition”?
  5. What are experimental hypothesis and null hypotheses? (HL Only)
  6. How and why are controls used in experiments?
  7. How why are single blind and double-blind techniques used in experiments?
  8. What ethical guidelines should researchers follow when conducting research?
  9. How and why are experimental design types used in experiments? (e.g. repeated measures, independent samples, matched pairs)
  10. How and why are allocation methods used in independent samples experiments? (e.g. random allocation and matched pairs/samples)
  11. What is representative sampling?
  12. How and why are sampling methods used in experimental (or any) studies?
  13. What are the strengths and limitations of the various sampling methods in psychological research?


*This is for Saint Maur students. The IB assessment of these learning outcomes is in mainly done through the Internal Assessment (IA).