THIS DATASET WAS LAST UPDATED AT 2:10 AM EASTERN ON JUNE 29

OVERVIEW

2019 had the most mass killings since at least the 1970s, according to the Associated Press/USA TODAY/Northeastern University Mass Killings Database.

In all, there were 45 mass killings, defined as when four or more people are killed excluding the perpetrator. Of those, 33 were mass shootings . This summer was especially violent, with three high-profile public mass shootings occurring in the span of just four weeks, leaving 38 killed and 66 injured.

A total of 229 people died in mass killings in 2019.

The AP's analysis found that more than 50% of the incidents were family annihilations, which is similar to prior years. Although they are far less common, the 9 public mass shootings during the year were the most deadly type of mass murder, resulting in 73 people's deaths, not including the assailants.

One-third of the offenders died at the scene of the killing or soon after, half from suicides.

About this Dataset

The Associated Press/USA TODAY/Northeastern University Mass Killings database tracks all U.S. homicides since 2006 involving four or more people killed (not including the offender) over a short period of time (24 hours) regardless of weapon, location, victim-offender relationship or motive. The database includes information on these and other characteristics concerning the incidents, offenders, and victims.

The AP/USA TODAY/Northeastern database represents the most complete tracking of mass murders by the above definition currently available. Other efforts, such as the Gun Violence Archive or Everytown for Gun Safety may include events that do not meet our criteria, but a review of these sites and others indicates that this database contains every event that matches the definition, including some not tracked by other organizations.

This data will be updated periodically and can be used as an ongoing resource to help cover these events.

Using this Dataset

To get basic counts of incidents of mass killings and mass shootings by year nationwide, use these queries:

Mass killings by year

Mass shootings by year

To get these counts just for your state:

Filter killings by state

Definition of "mass murder"

Mass murder is defined as the intentional killing of four or more victims by any means within a 24-hour period, excluding the deaths of unborn children and the offender(s). The standard of four or more dead was initially set by the FBI.

This definition does not exclude cases based on method (e.g., shootings only), type or motivation (e.g., public only), victim-offender relationship (e.g., strangers only), or number of locations (e.g., one). The time frame of 24 hours was chosen to eliminate conflation with spree killers, who kill multiple victims in quick succession in different locations or incidents, and to satisfy the traditional requirement of occurring in a “single incident.”

Offenders who commit mass murder during a spree (before or after committing additional homicides) are included in the database, and all victims within seven days of the mass murder are included in the victim count. Negligent homicides related to driving under the influence or accidental fires are excluded due to the lack of offender intent. Only incidents occurring within the 50 states and Washington D.C. are considered.

Methodology

Project researchers first identified potential incidents using the Federal Bureau of Investigation’s Supplementary Homicide Reports (SHR). Homicide incidents in the SHR were flagged as potential mass murder cases if four or more victims were reported on the same record, and the type of death was murder or non-negligent manslaughter.

Cases were subsequently verified utilizing media accounts, court documents, academic journal articles, books, and local law enforcement records obtained through Freedom of Information Act (FOIA) requests. Each data point was corroborated by multiple sources, which were compiled into a single document to assess the quality of information.

In case(s) of contradiction among sources, official law enforcement or court records were used, when available, followed by the most recent media or academic source.

Case information was subsequently compared with every other known mass murder database to ensure reliability and validity. Incidents listed in the SHR that could not be independently verified were excluded from the database.

Project researchers also conducted extensive searches for incidents not reported in the SHR during the time period, utilizing internet search engines, Lexis-Nexis, and Newspapers.com. Search terms include: [number] dead, [number] killed, [number] slain, [number] murdered, [number] homicide, mass murder, mass shooting, massacre, rampage, family killing, familicide, and arson murder. Offender, victim, and location names were also directly searched when available.

This project started at USA TODAY in 2012.

Contacts

Contact AP Data Editor Justin Myers with questions, suggestions or comments about this dataset at jmyers@ap.org. The Northeastern University researcher working with AP and USA TODAY is Professor James Alan Fox, who can be reached at j.fox@northeastern.edu or 617-416-4400.

Explore demographic data on the Massachusetts executive branch workforce. Track our progress toward our goals to reflect the diversity of the people we serve, and to stand out as an employer of choice.

As of September 4, eight people were killed in mass shootings in the United States in 2024. A total 1,159 victims were fatally injured during mass shootings in the United States between 1982 and September 4, 2024.

From 2015 to 2022, 23.9 people were wounded by an assault weapon in a mass shooting on average in the United States, compared to 1.1 who were wounded by another type of firearm.

April 2022

Dataset

This dataset was created by simeonwilson

Contents

ObjectiveA major reason for the loss of mobility in elderly people is the gradual loss of lean body mass known as sarcopenia. Sarcopenia is associated with a lower quality of life and higher healthcare costs. The benefit of strategies that include nutritional intervention, timing of intervention, and physical exercise to improve muscle loss unclear as finding from studies investigating this issue have been inconsistent. We have performed a systematic review and meta-analysis to assess the ability of protein or amino acid supplementation to augment lean body mass or strength of leg muscles in elderly patients.MethodsNine studies met the inclusion criteria of being a prospective comparative study or randomized controlled trial (RCT) that compared the efficacy of an amino acid or protein supplement intervention with that of a placebo in elderly people (≥65 years) for the improvement of lean body mass (LBM), leg muscle strength or reduction associated with sarcopenia.ResultsThe overall difference in mean change from baseline to the end of study in LBM between the treatment and placebo groups was 0.34 kg which was not significant (P = 0.386). The overall differences in mean change from baseline in double leg press and leg extension were 2.14 kg (P = 0.748) and 2.28 kg (P = 0.265), respectively, between the treatment group and the placebo group.ConclusionsThese results indicate that amino acid/protein supplements did not increase lean body mass gain and muscle strength significantly more than placebo in a diverse elderly population.

Statistics illustrates consumption, production, prices, and trade of Glass in The Mass in Lao People's Democratic Republic from 2007 to 2024.

This dataset contains key characteristics about the data described in the Data Descriptor Access to mass rapid transit in OECD urban areas. Contents:

    1. human readable metadata summary table in CSV format


    2. machine readable metadata file in JSON format

How racially diverse are residents in Massachusetts? This topic shows the demographic breakdown of residents by race/ethnicity and the increases in the Non-white population since 2010.

The data on mass shootings is from https://www.gunviolencearchive.org/ . This dataset on mass shootings for the period 2014-2023 was provided on Feb 19, 2024 by the Data Manager (Ms. Sharon Williams) at the Gun Violence Archive (https://www.gunviolencearchive.org/) on a data request. Minimal curation was done on this data – the date variable was split into year, month and day. See the codebook for full details.A mass shooting is defined as four or more people injured or killed, because of firearms, excluding the shooter.The curated datasets are included here along with a research question and guiding questions.For information of how this data is collected, go to: https://www.gunviolencearchive.org/explainerDefinition for mass shooting and mass murder from the above website is given verbatim below:Mass Shooting Methodology and Reasoning: Mass Shootings are, for the most part an American phenomenon. While they are generally grouped together as one type of incident they are several different types including public shootings, bar/club incidents, family annihilations, drive-by, workplace and those which defy description but with the established foundation definition being that they have a minimum of four victims shot, either injured or killed, not including any shooter who may also have been killed or injured in the incident. GVA also presents the count of Mass Murder which, like the FBI's definition is four or more victims, killed, not including the shooter. Mass Murder by gun is a subset of the Mass Shooting count.

This PXD project contains two projects published on ProteomicsDB (https://www.proteomicsDB.org) as integral part of the publication. The first project entitled 'human body map' (https://www.proteomicsdb.org/#projects/42) involves the analysis of 36 different human tissues and body fluids. The second project entitled 'Cellzome adopted' includes a collection of raw files which comprises identifications of 'missing proteins'.

Between 1982 and September 2024, 82 out of the 151 mass shootings in the United States were carried out by White shooters. By comparison, the perpetrator was African American in 26 mass shootings, and Latino in 12. When calculated as percentages, this amounts to 54 percent, 17 percent, and eight percent respectively. Race of mass shooters reflects the U.S. population Broadly speaking, the racial distribution of mass shootings mirrors the racial distribution of the U.S. population as a whole. While a superficial comparison of the statistics seems to suggest African American shooters are over-represented and Latino shooters underrepresented, the fact that the shooter’s race is unclear in around nine percent of cases, along with the different time frames over which these statistics are calculated, means no such conclusions should be drawn. Conversely, looking at the mass shootings in the United States by gender clearly demonstrates that the majority of mass shootings are carried out by men. Mass shootings and mental health With no clear patterns between the socio-economic or cultural background of mass shooters, increasing attention has been placed on mental health. Analysis of the factors Americans considered to be to blame for mass shootings showed 80 percent of people felt the inability of the mental health system to recognize those who pose a danger to others was a significant factor. This concern is not without merit – in over half of the mass shootings since 1982, the shooter showed prior signs of mental health issues, suggesting improved mental health services may help deal with this horrific problem. Mass shootings and guns In the wake of multiple mass shootings, critics have sought to look beyond the issues of shooter identification and their influences by focusing on their access to guns. The majority of mass shootings in the U.S. involve firearms which were obtained legally, reflecting the easy ability of Americans to purchase and carry deadly weapons in public. Gun control takes on a particular significance when the uniquely American phenomenon of school shootings is considered. The annual number of incidents involving firearms at K-12 schools in the U.S. was over 100 in each year since 2018. Conversely, similar incidents in other developed countries exceptionally rare, with only five school shootings in G7 countries other than the U.S. between 2009 and 2018.

Statistics illustrates market overview of glass in the mass in Democratic People's Republic of Korea from 2007 to 2024.

Liquid-chromatography-mass spectrometry (LC-MS) raw data sets from various instruments delivered in their native instrument format. 31 files in all. 7.5 GB data.

Sample mass spectrometry data from a bottom-up proteomics analysis of healthy human proteins. Original data source: https://zenodo.org/record/4274987.Data were collected on Thermo's Q-Exactive Plus mass spectrometer after digestion by trypsin.A human proteome FASTA file from UniProt is also included.

Validated analytical chemistry methods for measuring anatoxin-a in urine. This dataset is associated with the following publication: Cunningham, B., S. Lagon, W. Bragg, D. Jenkins-Hill, R. Shaner, and E. Hamelin. Detection of anatoxins in human urine by liquid chromatography triple quadrupole mass spectrometry and ELISA. Toxins. MDPI, Basel, SWITZERLAND, 16(3): 129, (2024).

Objective: We propose that citizens navigate an increasingly complex social and political world using a “cultural toolkit” shaped by firearms and gun violence. Young people in particular have experienced more mass shootings than any previous generation and have witnessed a lack of government response to these massacres. This article explores the attitudes that members of the Massacre Generation express about mass shooting prevention. Methods: We analyze data from several public opinion surveys conducted following major mass shootings in the United States using ordinary least squares and logistic regression. These surveys were fielded and sponsored by a variety of organizations and asked a nearly identical question about whether mass shootings can be prevented by societal and governmental action. Results: We find that the Massacre Generation is indeed more likely to think the government can prevent mass shootings by implementing stricter gun control laws. We find evidence of these attitudes in multiple public opinion surveys from 2012 to 2018. Furthermore, we find no age effect in multiple surveys conducted between 1999 and 2011, suggesting that these attitudes are a relatively new phenomenon. Conclusion: Young people today express that government regulation (i.e., stricter gun laws) can prevent gun violence, placing them at odds with older generations. We discuss the implications of our findings for gun policy development and the future of the gun debate.

This SuperSeries is composed of the SubSeries listed below. Refer to individual Series

Proteome-wide cross-linking mass spectrometry was performed on human K562 cell lysates. MS2-MS3 fragmentation strategy was used to aquire the XL-MS data. The raw files in this dataset are a subset of PXD013928.