Within-person variation in psychological qualities and their assessment Lecture 3, Psych R. Chris Fraley

Personality Processes Many of the questions that are asked in psychology are concerned with differences between people. Examples: –Are people who were physically abused as children more likely than those who were not to develop symptoms of psychopathology? –Are people who have warm and supportive relationships with their parents more likely than those who do not to be viewed as “good friends” among their peers? –Are people who play violent video games more likely than those who do not to behave aggressively toward people in real life?

It is not adequate to merely study people who play violent video games and examine their rate of their aggressive behavior. Why?

YesNo Yes 7 3 Plays Violent Video Games Behaves aggressively 7/10 aggressive

Answer: The counterfactual or comparison is missing. Thus, we compare people who do and people who do not play violent video games and study their relative rates of aggressive behavior. [2x2 lasers]

Between Persons Research This approach is typically referred to as nomothetic or between-persons research. Why? Because the comparisons are made with respect to different people; the differences are between persons. Nonetheless, we often assume that the association in question exists at the individual level too. (If people who play violent video games are more likely than those who do not to behave aggressively, presumably, for a given person, he or she will behave more aggressively on days on which he or she plays violent games compared to those days on which he or she does not.)

Is this reasonable? –Maybe Is it logically and statistically sound? –No Ecological fallacy – a logical fallacy, originally discussed in ecology, in which inferences about individuals are based exclusively on aggregate statistics about groups.

Violent video game playing Aggressive behavior Low High LowHigh

Violent video game playing Low High LowHigh Aggressive behavior

Violent video game playing Low High LowHigh Aggressive behavior

Violent video game playing Low High LowHigh Aggressive behavior

Violent video game playing Low High LowHigh Aggressive behavior

Summary To summarize: The between-persons association between two variables does not necessarily provide evidence for the association between those variables within persons. (And the flipside of this, of course, is that evidence of an association within a person does not provide evidence for that association between people.)

Ideographic As a result, many psychologists (especially in personality psychology) attempt to understand associations within individuals. Ideographic or within-persons focus: If it doesn’t work a certain way for you, why should you care?

Ideographic Methods There are many methods for studying the way in which psychological processes work for specific individuals. –Various terms: daily diary methods, experience sampling, ambulatory assessment, momentary ecological assessment Assess two or more psychological variables for a given person and examine the way in which those variables are related to one another within that person’s life.

On days in which I’m the happiest, what am I doing? Does the quality of my relationship with my wife impact my productivity at work? Do I perform better on exams when I study on a regular basis or when I cram before exams? Does my weight vary as a function of eating X, Y, and Z? How much weight should I expect to gain if I eat a pint of Ben and Jerry’s? My moods vary a lot. What kinds of events predict that variation? What kinds of daily events predict the quality of my sleep and the content of my dreams?

Major Project 2 - Ideographic Analyses One of the major projects you’ll be completing in this course involves within-person analyses. Specifically, you’ll be responsible for –Selecting a research question involving three or more variables –Collecting data on yourself over 30 days –Analyzing those data to reach conclusions about the association between variables in your own life

Personality Processes To assist in collecting and analyzing the data, we will use a web-based system called yourPersonality. Go to to login. Login using your class alias/ID (first week labs) as your User Name and your corresponding password

Our labs this week will focus on using yourPersonality and getting you started on the project. So please think between now and Friday what kind of questions you’d like to answer about yourself. Fri: (Homework due) Exploring yourPersonality and practice making modules. Begin making the modules for your project.