PSYCH 301W

Lesson 2: Introduction

Before you begin…read Chapter 2 in the textbook and be sure to look over the Paper Assignment #1. Paper 1 is due at the end of this week.

Developing a Research Hypothesis
In your textbook a hypothesis is defined as, “a specific and falsifiable prediction regarding the relationship between or among two or more variables”  We will return to the ideas of “specific” and “falsifiable” a little later.  For now, the reason that I put this up here is to point out anyone can generate a hypothesis about any two or more variables.

We need to be specific about how we describe our variables.  The textbook mentions the idea of predictor and outcome variables, and the idea of independent and dependent variables (commonly written as IV and DV).  Let’s take an example and try some of these variable names on for size.

My two variables are: Walking Speed (in miles per hour) and Mood (an emotional state involving either positive (e.g. happy, excited) or negative (e.g. sad, angry) emotions).  At this point I can generate several hypotheses related to these variables. 

Hypothesis 1: People in positive moods will walk faster than people in negative moods.
Hypothesis 2: People who walk faster will experience more positive moods than will people who walk more slowly.

At this point you may be thinking, “Great, you said the same thing twice.  That’s not very interesting.”  In fact these hypotheses actually imply two different psychological processes.  (Huh?)  What I mean is that Hypothesis 1 implies that mood is influencing how fast people are walking.  Mood is causing a change in walking speed.  In this case, mood is the predictor variable and walking speed is the outcome variable.  For Hypothesis 2 it’s implied that walking speed (now the predictor variable) actually influences mood (the outcome variable).  More importantly, the implications for the processes at work are very different.  For Hypothesis 1, it could be that happy people tend to expend more energy overall than do sad people, and this is causing them to walk faster.  For Hypothesis 2, the act of physical exertion is implied to change people’s mood in a positive direction (exercise makes people happy, perhaps).