How homicide spreads like an infectious disease

The Gangs of New York:
An Informal History
of the Underworld

by Herbert Asbury

Order new or used from
Powell's Books
I remember reading the 1927 book, Gangs of New York by Herbert Asbury and thinking of how the circumstances of poverty and crowding led to so much of the development of gangs, starting with groups of immigrant thugs and bullies and ending up many years later with the Mafia and other "professional" crime groups.

 If you haven't read Asbury's book but have seen the movie, while a few of the historical characters (yes, Bill the Butcher was a real person) ended up in the Martin Scorsese movie, unlike the movie, the book is an "informal" history of people living in the Five Points slum of New York.  

 Jump forward to today and we still have far too many marginalized youth living in or near poverty who feel the gang life is their only way to achieve anything.  This doesn't excuse their acts, but it does explain how they get to where they are.

 This story is another example of how statistical techniques combined with a computer can be put to use to predict patterns of criminal and anti-social behavior - and perhaps giving us a handle on the problem.

 Here's the report, again with a link to the original studies in the attribution lines.
*  *  *  *  *

Can science predict gang killings?

"In the places gang homicides move into, we see other types of homicide
-- specifically, revenge and drug-related killings -- also clustering."

Gang slayings move in a systematic pattern over time, spreading from one vulnerable area to the next like a disease, finds a groundbreaking study by Michigan State University criminologists and public health researchers.

Their findings, published online in the American Journal of Public Health, could help pave the way for communities to one day anticipate and ultimately prevent gang-related homicides and other violent crimes.

Gang membership growing nationally
There were 2,363 gang-related killings in the United States in 2012, the highest number in at least six years, according to the latest available estimates from the Department of Justice. Gang membership also increased, to 850,000 in 2012 from 788,000 in 2007.

"We've shown that there is a potentially systematic movement of gang-related homicides," said April Zeoli, associate professor of criminal justice and lead investigator on the study. "Not only that, but in the places gang homicides move into, we see other types of homicide -- specifically, revenge and drug-related killings -- also clustering. Taken together, this provides one piece of the puzzle that may allow us to start forecasting where homicide is going to be the worst -- and that may be preceded in large part by changes in gang networks."

Using police data from Newark, New Jersey, Zeoli and fellow MSU researchers Sue Grady, Jesenia Pizarro and Chris Melde were the first to show, in 2012, that homicide spreads like infectious disease. Similar to the flu, homicide needs a susceptible population, an infectious agent and a vector to spread. (The infectious agent could be the code of the street -- i.e., guarding one's respect at all cost, including by resorting to violence -- while the vector could be word of mouth or other publicity, Zeoli said.)
*  *  *  *  *
SIDEBAR:
Juvenile gang members in US top 1 million, new study finds
There are over one million juvenile gang members in the U.S., more than three times the number estimated by law enforcement, according to a recent study.  "Gang membership between ages 5 and 17 years in the United States," published in the Journal of Adolescent Health, challenges many popular demographic stereotypes about gangs.
The study found that an average of 2 percent of youth in the U.S. are gang members, with involvement highest at age 14, when about 5 percent of youth are in gangs. Youth in gangs also come from all types of backgrounds.
"The public has been led to believe that gang members are black and Latino males and that once someone joins a gang they cannot leave a gang, both of which are patently false," said David Pyrooz, assistant professor of Criminal Justice at Sam Houston State University.
"Being a gang member is not all that it is cracked up to be, which is something kids realize once they get involved and find out that the money, cars, girls, and protection is more myth than reality," said Pyrooz.
Source:  Materials provided by Sam Houston State University. David C. Pyrooz, Gary Sweeten. Gang Membership Between Ages 5 and 17 Years in the United States. Journal of Adolescent Health, 2015
*  *  *  *  *

With the new study, the interdisciplinary team of researchers analyzed the Newark data to gauge whether specific types of homicide cluster and spread differently. In addition to gang-related murders, the researchers looked at homicide motives such as robbery, revenge, domestic violence and drugs. These other motive types were not directly connected to gang participation.

The study found that the various homicide types do, in fact, show different patterns. Homicides stemming from domestic violence and robberies, for example, show no signs of clustering or spreading out.

"Gang-related killings were the only type of homicide that spread in a systematic pattern."

Gang-related killings were the only type of homicide that spread in a systematic pattern. Specifically, there were four contiguous clusters of gang-related homicides that started in central Newark and moved roughly clockwise from July 2002 through December 2005.

Revenge and drug-motivated homicides unrelated to gang activity did not spread out, but they did cluster. Interestingly, they clustered in the same general area as the gang murders.

"By tracking how homicide types diffuse through communities and which places have ongoing or emerging homicide problems by type, we can better inform the deployment of prevention and intervention efforts," the study says.

Related stories:
Story Source:  Materials provided by Michigan State University. April M. Zeoli, Sue Grady, Jesenia M. Pizarro, Chris Melde. Modeling the Movement of Homicide by Type to Inform Public Health Prevention Efforts. American Journal of Public Health, 2015

Comments

Post a Comment

Popular posts from this blog

How the lives of Georgian gaolbirds and highwaymen shaped modern Britain

Image
Writing historical fiction requires solid research of available materials and databases.  The key word here is available.   So news of a new publicly accessible database that allows an author to research a very interesting past era is priceless almost beyond words.   I expect some exciting fiction to come out of this announcement. Here's the story, with a link to the source in the attribution. *  *  *  *  * London Lives, a landmark project led by Professor Bob Shoemaker from the University of Sheffield and Professor Tim Hitchcock from the University of Sussex, has uncovered a mass of extraordinary new evidence which reveals how the lives of thousands of 18th-century poor and criminal Londoners helped shape modern Britain. Based on evidence made available in a publicly available database, the study sheds new light on the everyday lives of thieves, prostitutes, vagrants, highwaymen, con-men, paupers and jailbirds, revealing how their daily fight for survival led to t
Read more

An unexpected way to recover from a breakup

Image
Breaking up is truly hard to do. And recovery from a breakup can be even harder. Your friends may counsel you to put the whole thing out of your mind. But new research suggests that repeatedly reflecting on a break-up -- even through participation in a research study -- actually speeds emotional recovery. "Breakups are ubiquitous -- most adults have experienced at least one in their life -- and are typically very distressing," says Grace Larson of Northwestern University. After studying divorce and breakups for years using longitudinal, multi-method designs, Larson and her then-adviser David Sbarra of the University of Arizona wanted to study whether these research techniques on their own were affecting participants. One concern they had was that the studies could be harming participants, Larson says. "At first glance, it might seem like repeatedly reminding participants that they had just broken up -- and asking them to describe the breakup over and over --
Read more

Greek Bronze Age ended 100 years earlier than thought

Image
Source: www.shef.ac.uk The charred remains of Assiros Toumba in Greece. Writing historical fiction set in the Greek Bronze Age?  Or simply enjoy reading this genre'?  Here's a study you may find interesting. C onventional estimates for the collapse of the Aegean civilization may be incorrect by up to a century, according to new radiocarbon analyses. While historical chronologies traditionally place the end of the Greek Bronze Age at around 1025 BCE, this latest research suggests a date 70 to 100 years earlier. www.weather-forecast.com Archaeologists from the University of Birmingham selected 60 samples of animal bones, plant remains and building timbers, excavated at Assiros in northern Greece, to be radiocarbon dated and correlated with 95.4% accuracy using Bayesian statistical methodology at the University of Oxford and the Akademie der Wissenschaften Heidelberg, Germany. Researcher Dr Ken Wardle says, 'These new results tell a story that is totall
Read more

Mood Instability and Your Characters

Image
You're putting together a character who's mood simply bounces all over the place, happy one moment, in a fit of rage the next.  Researchers at King's College London note that this sort of mood instability is part of a number of mental health disorders.  So how do you structure the personality and behavior of a character like this?  Below is the King's College report, along with a brief description from mentalhealth.com, of typical behavior, sometimes in the extreme, of a person who is very emotionally unstable.  This is offered strictly as a guide for crafting character in fiction - and NOT for the amateur diagnosis of the state of someone's mental health.  That is always best left to trained professionals. Another note about emotionally unstable behavior:  as any parent will tell you, this is how adolescents and teen-agers often behave.  It's a normal part of growing up - but it is a matter of degree .  In the extreme, however, this behavior can be diag
Read more

Remember faces but not names? You got it wrong.

Image
Source:   Daily Excelsior So, you think you're good at remembering faces, but terrible with names? New research has revealed we are actually better at remembering names than faces The cringe-worthy experience of not being able to remember an acquaintance's name leads many of us to believe we are terrible with names. However, new research has revealed this intuition is misleading; we are actually better at remembering names than faces. With the Christmas party season fast approaching, there will be plenty of opportunity to re-live the familiar, and excruciatingly-awkward, social situation of not being able to remember an acquaintance's name. This cringe-worthy experience leads many of us to believe we are terrible at remembering names. However, new research has revealed this intuition is misleading; we are actually better at remembering names than faces. The authors of the study, from the University of York, suggest that when we castigate ourselves f
Read more