Skip to content

A clustering method for graphical handwriting components and statistical writership analysis

Journal: Statistical Analysis and Data Mining: The ASA Data Science Journal
Published: 2020
Primary Author: Amy M. Crawford
Secondary Authors: Nicholas S. Berry, Alicia L. Carriquiry
Research Area: Handwriting

Handwritten documents can be characterized by their content or by the shape of the written characters. We focus on the problem of comparing a person’s handwriting to a document of unknown provenance using the shape of the writing, as is done in forensic applications. To do so, we first propose a method for processing scanned handwritten documents to decompose the writing into small graphical structures, often corresponding to letters. We then introduce a measure of distance between two such structures that is inspired by the graph edit distance, and a measure of center for a collection of the graphs. These measurements are the basis for an outlier tolerant K‐means algorithm to cluster the graphs based on structural attributes, thus creating a template for sorting new documents. Finally, we present a Bayesian hierarchical model to capture the propensity of a writer for producing graphs that are assigned to certain clusters. We illustrate the methods using documents from the Computer Vision Lab dataset. We show results of the identification task under the cluster assignments and compare to the same modeling, but with a less flexible grouping method that is not tolerant of incidental strokes or outliers.

Related Resources

CSAFE 2021 Field Update

CSAFE 2021 Field Update

The 2021 Field Update was held June 14, 2021, and served as the closing to the first year of CSAFE 2.0. CSAFE brought together researchers, forensic science partners and interested…
Handwriting Analysis at CSAFE

Handwriting Analysis at CSAFE

This CSAFE webinar was held on March 11, 2021. Presenter: Alicia Carriquiry Distinguished Professor and President’s Chair in Statistics, CSAFE Director Presentation Description: Forensic handwriting analysis relies on the principle…
Bayesian hierarchical modeling for the forensic evaluation of handwritten documents

Bayesian hierarchical modeling for the forensic evaluation of handwritten documents

The analysis of handwritten evidence has been used widely in courts in the United States since the 1930s (Osborn, 1946). Traditional evaluations are conducted by trained forensic examiners. More recently,…
CSAFE 2020 All Hands Meeting

CSAFE 2020 All Hands Meeting

The 2020 All Hands Meeting was held May 12 and 13, 2020 and served as the closing to the last 5 years of CSAFE research and focused on kicking off…