Sociation Today® 
The Official Journal 
The North Carolina 
Sociological Association: A 
Refereed Web-Based 
ISSN 1542-6300
Editorial Board:

George H. Conklin,
 North Carolina
 Central University

Richard Dixon,

Chien Ju Huang,
 North Carolina
 Central University

Ken Land,
 Duke University

Miles Simpson,
 North Carolina
 Central University

Ron Wimberley
 N.C. State University

Robert Wortham,
 North Carolina
 Central University




Volume 2, Number 2
Fall 2004
Article Review:

The Impact of Density: The Importance of Nonlinearlity and Selection on Flight and Fight Responses.

Reviewed by George H. Conklin

Background: Many journals have book reviews. However, in the sciences the most common form of communication is not books, which are out of date when published, but articles. Many books are based on articles and enlarged often beyond what is required. However, the opposite is also true: there are many important articles which address basic issues in the social sciences that have not been made into books, but perhaps should be. In order to draw attention to important articles which address basic issues which sociologists are interested in, Sociation Today will review articles rather than books. 

In this issue of Sociation Today, the review deals with the concept of density and how crowding affects the human animal.  As with the supply of public services, the effects of density on behavior are nonlinear  (see the nonlinear relationship between urban costs and population density).  There is also self-selection because people who feel that they are crowded move to less dense locations. Environment affects human behavior but simplistic measures tend to obscure the relationship. 

The Impact of Density:  The Importance of Nonlinearity and Selection on Flight and Fight Response,  by  Wendy C. Regoeczi,  in  Social Forces 81, 2002, pp. 505-530.

    Researchers in the social sciences have long tried to explain the effects of urbanization on the human animal. Of special interest has been the observed rates of crime and deviant behavior found in cities.  In the United States city crime rates are higher than suburban rates, which in turn are higher than rural rates.  Studies on animals as well as observations of human behavior have been used to examine density and human pathology, but results have been mixed.  Regoeczi shows that the effect of crowding on human behavior is non-linear.  Further, people who suffer from the effects of crowding self-select into lower density living conditions to self-treat their condition.

    Two major theories have developed to explain the effects of density on human behavior.  Wirth’s (1938) is the most common with his famous statement that size, density and heterogenity explain the effects of urban life on the human animal.  The experiments done by Milgram (1970) suggest that when people are confronted with a large number of strangers in everyday life, they tend to withdraw and take less interest in the community in order to protect themselves from overload.  Wolfgang (1970), among others, suggests that urban withdrawal and anomie  resulting from density explains higher urban crime rates. 

    Animal studies made famous by Calhoun (1962) show that crowding in the animal world results in what he calls the behavioral sink.  Normal behavior and reproductive habits fail.  Aggressive behavior increases when density passes a certain point as animals compete for resources.  In the experience of the reviewer, those who deny any possible connection between any human behavior simply say that humans are not animals so there can be nothing learned from animal experiments.  However, human animals do seem to exhibit much lower fertility rates in cities than is true in rural areas. 

    Those who have looked empirically at human behavior and density (or crowding) have come to different conclusions.  Regoeczi states that the inconsistent results that plague the density literature are due to a misspecification of how density effects operate.  In particular, there are several issues with respond to how density effects are specified that, left unaddressed, lead to serious misrepresentations of the relationship of density to pathology.  These issues pertain to self-selection and nonlinear effects of density on social behavior (p. 507).

    Using data from the Toronto Mental Health and Stress study (Turner and Wheaton 1992), Regoeczi looks at crowding in housing using the measure of persons per room.  Measures of withdrawal came from questionnaire responses to a series of questions about showing affection and love.  Aggression was measured from a series of questions asking about how aggressive people felt towards other.  Control variables included marital status, household income, ethnicity and gender.  Structural equations developed by Bollen (1995) were used to detect nonlinear relationships.

    A graph of the relationship between crowding and withdrawal (see below) shows a nonlinear relationship. 

Source: Regoeczi 2002, p. 517.

There is an optimal relationship between crowding and withdrawal.  The optimal point is 1.18 persons per room.  This relationship holds even when the control variables are introduced.  “The threshold for aggression is identical to that for withdrawal:  1.18 persons per room.  After this point, the deleterious effect of density begins to take off and increased crowding leads to more aggressive responses among individuals.” (p. 521.) 

    Additional analysis was done to see the effects of self-selection and crowded conditions.  The author finds that individuals with problems with aggressive or withdrawal behavior also self select themselves into lower density housing.  This result has in the past tended to lower the correlations which exist between aggression and crowding, hiding the relationship if self selection is not taken into account. 

    In conclusion, not only does self selection tend to hide the relationship between aggression and crowding so also the tendency in the social sciences to use correlations to measure effect tends to hide the actual situation.  “In particular, if the relationship is modeled as linear when it is in fact nonlinear, the significance of the effects of density are likely to be to understated or missed entirely.” (p. 525). 

    Although the analysis is limited to one city and does not consider the effects of overall population density on human behavior, the author does show that when people feel crowded, they tend to withdraw from the situation to find less stressful situations.  This response is probably normal for human and animal behavior but it will tend to obscure simple correlations between aggression or withdrawal and observed behaviors. 

    This study does not address directly the issue of why densities began to decline  in American cities once transportation developed which allowed the human animal avoid very dense living conditions of the pre-1880 city.  It does however give us clues that when people do not feel comfortable in a dense situation, they tend to withdraw.

    In the future self-selection and the non-linear relationship between density and behavior must be considered as a factor in reducing the observed correlations between the human animal and crowding behaviors.  Environment does affect human behavior as well as that of animals.  It cannot continue to be ignored in the future simply because such research in the past has been too simplistic. 


Bollen, Kenneth A. 1995.  “Structural Equation Models that are Nonlinear in Latent Variables:  A Least Squares Estimator."  Pp. 223-251 in Sociological Methodology, 1995, edited by Peter V. Marsden. Blackwell. 

Calhoun, John B. 1962.  “Population Density and Social Pathology.”  Scientific American 206:139-148.

Milgram, Stanley. 1970.  “The Experience of Living in Cities.”  Science 167:1461-1468.

Regoeczi, Wendy C. 2002.   “The Impact of Density:  The Importance of Nonlinearity and Selection on Flight and Fight Response.” Social Forces 81:505-530.

Turner, R. Jay and Blair Wheaton.  1992. “Psychiatric Distress and the Use and Abuse of Alcohol and Drugs.”  Social Sciences and Humanities Research Council of Canada. 

Wolfgang, Marvin E. 1970. “Urban Crime.”  In The Metropolitan Enigma, edited by James Q. Wilson.  Doubleday Anchor.

Wirth, Louis. 1938. “Urbanism as a Way of Life.” American Journal of Sociology 44:1-24.

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