About This Project

In much of psychological research, expected effects are not shown by everybody, but just by a subset of participants. We aim to identify whether this subset of participants consists of the same people across theoretically-unrelated psychological effects (i.e., whether psychology effects are driven by a small portion of the population). If so, this may have profound implications for how we understand research findings in psychology and beyond.

Ask the Scientists

What is the context of this research?

In psychology, there are many different types of measures and procedures. Psychologists assume that effects seen in these procedures apply to at least a majority of the population. In recent research, Jamie and his colleagues have found that this was not the case in one such procedure. When asked to report on attitudes to different topics (e.g., politics), they found that about 15% of people tended to show effects in general, regardless of the attitude topic being assessed; the rest of the people involved never showed effects. Similar subset effects have been documented for several other procedures too. We want to test whether the people who drive effects are the same people across different, unrelated tasks.

What is the significance of this project?

Although many psychologists are aware that a lot of their measures show these subset effects, we often just ignore them or consider them part of random variation. If we demonstrate that effects in various measures are driven by the same people, then we will effectively demonstrate that much of psychology has only been studying a subset of the population. This would open up a whole new range of questions. Why do only these people show an effect? How can we also study the portion of participants who don't? Are some measures more susceptible to this problem than others? Because this issue is potentially applicable to many different fields of psychology, and because it may threaten the validity of our measures, this project will be of great significance to the discipline.

What are the goals of the project?

The proposed experiment is the first step in a bigger research agenda we plan. We will get participants to complete popular measures from various areas of psychology (e.g., an evaluative conditioning paradigm [learning research], an aggression priming paradigm [media effects research], an implicit measure of attitudes [social psychology], a mood induction task [emotion research]). These will be measures which (i) are widely used in their field, (ii) are used regularly in online research, (iii) do not take much time to complete, and (iv) whose results are assumed to apply to most of the population being studied. We will then examine (i) whether scores in these unrelated tasks are correlated, and (ii) whether the participants who respond most strongly are consistent across tasks.