Mass shootings – a short research Background A subset of national homicides that captures both the headlines and the attention of policy makers is that of mass shootings – in schools, workplaces, places of worship, grocery stores, and elsewhere. Definitions are not always consistent, but a common definition (and the one used by the primary database for this project) of a mass shooting is: a multiple homicide incident in which four or more victims are murdered with firearms — not including the offender(s) — within one event, and at least some of the murders occurred in a public location or locations in close geographical proximity (e.g., a workplace, school, restaurant, or other public settings), and the murders are not attributable to any other underlying criminal activity or commonplace circumstance (armed robbery, criminal competition, insurance fraud, argument, or romantic triangle). Following each mass shooting, there are inevitably calls for policy makers to “do something” whether it is to tighten gun control laws, improve mental health programs, provide armed security (perhaps including teachers) at schools, increase active shooter response training, redesign school or office buildings to be more secure, or something else. Despite recurring calls to “do something,” few meaningful policies to stop these mass shootings have been broadly implemented, and one reason for this is that there does not appear to be a consensus on the root cause(s) of the problem: is it about gun control, or is it about mental health, or is it about armed security, or something else? Maybe it’s about all of these, but which ones are the dominant underlying factors? Assignment The purpose of this assignment is to introduce you to formulating hypotheses that can be resolved (typically by refuting them through the scientific method) using quantitative methods. You do not have to resolve the hypotheses that you formulate, but you should think about them deeply enough to imagine how you might ultimately use quantitative data to resolve them · Task: First, read the information at the following two web sites related to mass shootings that employ an interactive online database: · https://www.theviolenceproject.org/mass-shooter-database/ · https://projects.voanews.com/mass-shootings/ · Task: Use the interactive online database from these websites to formulate hypotheses about the “common denominators” of mass shootings. In other words, develop at least one (or more) hypothesis about the relationships between some of the potential variables related to mass shootings. These will likely be hypotheses that you think can be refuted; therefore they are likely to be worded oppositely of what you think (or hope) is true. (I know this seems strange, but the sooner that you understand this, the better.) · Suggestio ...

1. Mass shootings – a short research
Background
A subset of national homicides that captures both the headlines
and the attention of policy makers is that of mass shootings – in
schools, workplaces, places of worship, grocery stores, and
elsewhere.
Definitions are not always consistent, but a common definition
(and the one used by the primary database for this project) of a
mass shooting is:
a multiple homicide incident in which
four or more victims are murdered with firearms — not
including the offender(s) —
within one event, and at least some of the murders
occurred
in a public location or locations in close geographical
proximity (e.g., a workplace, school, restaurant, or other public
settings), and the
murders are not attributable to any other underlying
criminal activity or commonplace circumstance (armed robbery,
criminal competition, insurance fraud, argument, or romantic
triangle).
Following each mass shooting, there are inevitably calls for
policy makers to “do something” whether it is to tighten gun
control laws, improve mental health programs, provide armed
security (perhaps including teachers) at schools, increase active
shooter response training, redesign school or office buildings to
be more secure, or something else.
Despite recurring calls to “do something,” few meaningful
policies to stop these mass shootings have been broadly
implemented, and one reason for this is that there does not
appear to be a consensus on the root cause(s) of the problem: is
it about gun control, or is it about mental health, or is it about

2. armed security, or something else? Maybe it’s about all of
these, but which ones are the dominant underlying factors?
Assignment
The purpose of this assignment is to introduce you to
formulating hypotheses that can be resolved (typically by
refuting them through the scientific method) using quantitative
methods. You do not have to resolve the hypotheses that you
formulate, but you should think about them deeply enough to
imagine how you might ultimately use quantitative data to
resolve them
·
Task: First, read the information at the following two
web sites related to mass shootings that employ an interactive
online database:
·
https://www.theviolenceproject.org/mass-shooter-
database/
·
https://projects.voanews.com/mass-shootings/
·
Task: Use the interactive online database from these
websites to formulate hypotheses about the “common
denominators” of mass shootings. In other words, develop at
least one (or more) hypothesis about the relationships between
some of the potential variables related to mass shootings. These
will likely be hypotheses that you think can be
refuted; therefore they are likely to be worded
oppositely of what you think (or hope) is true. (I know this
seems strange, but the sooner that you understand this, the
better.)
· Suggestion for hypothesis wording: Suppose that you hope to
show that more deaths (in mass shootings) have been caused by
assault rifles than by other weapons. Then your hypothesis
would be something like “the number of deaths caused by

3. assault rifles is (statistically) the same as caused by other
weapons” (i.e., something that you hope to refute, thereby
supporting what you hoped to show).
· These hypotheses should be amenable to
quantitative resolution.
· These hypotheses should be ones that you
think could reasonably be addressed by the full offline
database (refer to the appendix for more details about the full
database), although perhaps not by the interactive online
database. Note that you do not need to verify that the full
database will actually resolve your hypotheses, but only that
you
think it might.
· Avoid “obvious” hypotheses such as shooters are equally
distributed among women and men (which is easily refuted), or
other factors already addressed in the websites. Develop your
own ideas.
· Avoid “definitional” hypotheses such as most mass shootings
kill fewer than 4 victims (because this is refuted by the
definition of a mass shooting for this database).
·
Task: Identify at least one “important” question that
policy makers should want answered but cannot be answered
from the data in this database (even the full database). The
purpose for this is to recognize that even very good databases
cannot address all important questions on a topic.
·
Optional task: If you can, identify a data source that
could be useful in addressing the important question that you
raise. I am not suggesting that any of the following would
actually be useful, but there are a multitude of related web sites
such as:

4. ·
https://www.gunviolencearchive.org
·
https://everytownresearch.org/maps/mass-shootings-in-
america/
·
https://www.npr.org/sections/ed/2018/08/27/640323347/the-
school-shootings-that-werent
·
https://www.fbi.gov/file-repository/active-shooter-
incidents-20-year-review-2000-2019-060121.pdf/view
·
https://www.rand.org/research/gun-policy.html
·
https://ourworldindata.org/homicides
Task: Finally, summarize your findings in a short paragraph
Use the scientific method; avoid advocacy
This is a research topic where many people, perhaps you too,
have strong opinions. There is nothing inherently wrong with
that, but I expect for you to perform a neutral, data-driven
approach where hypotheses may eventually be accepted or
rejected. It is okay if your hypotheses come from your
previously held viewpoints, and great if they contradict some of
your previously held assumptions, but this assignment is not a
forum for you to espouse your personal beliefs on this subject.
Appendix: Variables in the full (offline) database
This a list of the variables in the full (offline) database, of
which the interactive online database is only a partial view.
This is provided only to give you an idea of some of the
hypotheses that could be resolved from the complete database,
as well as some hypotheses that still could not be resolved,
Case #

5. Shooter Last Name
Shooter First Name
DATE
Full date
Day of the week
Day
Month
Year
Days since previous shooting
LOCATION
Shooting location address
City
State
Region
Urban, suburban, or rural area
Location type
Insider / Outsider
Bifurcated (multiple locations)
Location 2 (if bifurcated)
Armed person on the scene when shooting started
Specify armed person on scene (if applicable)
VICTIMS
Number killed
Number injured
Kidnapping or hostage element
OFFENDER BACKGROUND
Age
Gender
Race
Immigrant
Sexual orientation
Religion

6. Education
School performance
School performance specified
Birth order
Number of siblings
Number of older siblings
Number of younger siblings
Relationship status
Children (shooter was a parent)
Employment status
Employment type
Military service
Military branch
Community involvement (participation in civic life and
membership in local clubs and organizations)
Community involvement specified
CRIME AND VIOLENCE
Criminal record / prior police contact
Previous homicide(s)
History of physical violence
History of domestic abuse (including non-physical forms of
abuse)
Domestic abuse type 1
Domestic abuse type 2
Domestic abuse type 3
History of sexual offenses (rape, molestation, indecent
exposure, child pornography, sexual harassment, or other acts
with a sexual motivation)
Gang association
Terror group association
Hate group association
Played violent video games (first-person shooters)
Bully
TRAUMA AND CRISIS

7. Bullied
Raised by single parent
Suicide of parent
Childhood trauma
Childhood socioeconomic status
Adult trauma
Recent or traumatic breakup
Recent or traumatic change in work status or trouble at work
Signs of being in crisis (notable behavioral changes)
Timeframe of when signs of crisis began
Signs of crisis specified
Recent or ongoing stressor
Inability to perform daily tasks
Notably depressed mood
Unusually calm or happy
Rapid mood swings
Increased agitation
Abusive behavior
Isolation
Losing touch with reality
Paranoia
HEALTH AND MENTAL HEALTH
Suicidality
Hospitalization for psychiatric reasons
Voluntary or involuntary hospitalization
Prior counseling
Voluntary or mandatory counseling
Prescribed psychiatric medication
Treatment (counseling, medication, hospital) in the 6 months
prior to shooting
Mental illness
Known family history of mental health issues
Autism spectrum disorder
Substance use and abuse

8. Health issues
Specify health issues
GRIEVANCE AND MOTIVATION
Known prejudices 1 (not motive)
Known prejudices 2 (not motive)
Known prejudices 3 (not motive
Motive: Racism
Motive: Religious hate
Motive: Misogyny
Motive: Homophobia
Motive: Employment issue (fired, lost promotion)
Motive: Economic issue (issues with money)
Motive: Legal issue
Motive: Relationship issues (break-up, separation)
Motive: Interpersonal conflict (non-domestic, with coworkers,
friends, family)
Motive: Fame-seeking
Motive: Other
Motive: Unknown
Domestic spillage
Role of psychosis in the shooting
SOCIAL CONTAGION
Social media use related to shooting
Leakage (communication to a third party of an intent to do
harm) prior to the shooting
Leakage - How?
Leakage - Who?
Leakage - Specific?
Additional leakage - How?
Additional leakage - Who?
Additional leakage - Specific?
Interest in past mass violence
Relationship with other shooting(s)
Specify relationship to other shooting(s)
Legacy token (left something behind)

9. Connection to pop culture
Specify pop culture connection
Well-planned
Performance ("will to representation")
WEAPONS
Notable or obsessive interest in firearms
Firearm proficiency
Total weapons brought to the scene
Other weapons or gear
Specify other weapons or gear
RESOLUTION OF CASE
On scene outcome
Attempt to flee
Insanity defense at trial
Criminal sentence
FIREARMS TAB (guns used for each shooting in database)
Make and model
Classification
Caliber
Gun used in shooting
Modified
Extended magazine (replacing the standard magazine with one
of a higher capacity)
When obtained
Legal purchase
Illegal purchase
Assembled with legal parts
Gifted
Theft
Unknown

10. VICTIMS TAB (individuals killed for each shooting in
database)
Age
Gender
Race
Knew Perpetrator
If known, relationship with perpetrator
Life expectancy
Years Lost
COMMUNITY TAB (Shootings 1995 and after only)
Location
Shooting Start Time
Shooting End Time
Time of Day (Start Time)
Zip Code
Total Population (U.S. Census)
Median Age
% White Alone
% Female Household
% Rental Units
% Employed
% High School Graduate
% College Graduate
% Without Health Insurance
Nearest Hospital (in Miles)
N Mental Health Providers in Zip Code
N Gun Stores in Zip Code
Size of Police Department
Homicide Rate (FBI UCR)