Counting the uncounted: How many were killed in Guatemala, 1978-1995?

2026-06-04

AI Summary

This study addresses the undercounting of victims in the Guatemalan Civil War (1978–1995), where some fatalities were absent from all existing records. To estimate the number of unrecorded deaths, the authors propose a parametric multiple capture–recapture model based on a three-set Venn diagram structure. Leveraging three independent victim lists that yield seven observable overlap cells, the method employs either a Bayesian or likelihood-based framework to infer the unobserved “empty cell” of the underlying multinomial distribution. Building upon a confirmed count of 47,803 documented victims, this approach provides the first systematic quantification of individuals entirely missing from historical records, thereby substantially enhancing the completeness and accuracy of total mortality estimates for the conflict.

Abstract

In various application domains, there is a certain `null cell', inside a multinomial setup, where observations are recorded for the other cells, but where one cannot count the number of occurrences for the null cell. I develop inference theory for assessing such unknown numbers, counting the uncounted, in situations where counts are available for the other cells, via parametric modelling. The methods are used to estimate the number of persons killed in Guatemala during the Genocidio guatemalteco years 1978--1995. There are three carefully curated lists of killed people, where the information can be mapped to a Venn diagram with $2^3=8$ cells. Summing over the seven observed cells, $R=\hbox{47,803}$ killed individuals can be identified, but how big is $N_{0,0,0}$, and hence $N=N_{0,0,0}+R$?

Problem

• null cell
• multinomial setup
• unobserved counts
• missing data
• capture-recapture

Innovation

• null cell estimation
• multinomial modeling
• capture-recapture
• parametric inference
• Venn diagram decomposition