Chapter 13. Social Psychology

Social Psychology

13.1 Section Title

Topic: The Size of Social Groups

Statistical Concepts Covered: In this applet, you’ll expand on your knowledge of correlations by using them in regards to regression and making predictions.

Introduction

In this applet we will utilize the data collected from a study by Dunbar (2003) to test the social brain hypothesis, the belief that the human brain, specifically the neocortex, has increased in size to accommodate the cognitive demands of being in large social groups. In order to look at human evolution in this way, we will explore how humans, hominoids, and simians compare in terms of neocortex ratio and social group size. Simians are “higher” primates, such as apes and monkeys, while hominoids are those resembling humans (e.g., Neanderthals), but are not what we refer to as humans. Neocortex ratio is the ratio of the size of the neocortex to the rest of the brain. A 1:1 ratio (represented as simply 1 on the X-Axis in the graphs in this applet) would mean that the neocortex makes up half of the brain, while a 2:1 ratio (represented by 2) would mean that the neocortex is twice the size of the rest of the brain.

Richard Alan Hullinger, Indiana University, Bloomington
Melanie Maggard, University of the Rockies