Edna Schechtman (1948–2022)
Edna Schechtman (1948–2022) was a distinguished Israeli statistician and biostatistician whose work formed a critical bridge between theoretical mathematics and practical applications in the life sciences. While often categorized as a statistician, her primary impact was felt in the fields of biology, medicine, and genetics, where her methodologies provided the rigor necessary for interpreting complex biological data.
As a Professor at Ben-Gurion University of the Negev (BGU), she became a global authority on the "Gini Index" and its applications, fundamentally changing how researchers measure variability and inequality across diverse scientific disciplines.
1. Biography: Early Life and Academic Trajectory
Edna Schechtman was born in 1948 in Israel, a member of the generation that grew up alongside the fledgling state. Her academic journey was marked by a steady progression through Israel’s most prestigious institutions before she sought international specialization.
Education:
- She earned her B.Sc. in Mathematics and Statistics from the Hebrew University of Jerusalem, followed by an M.Sc. in Statistics from the Technion – Israel Institute of Technology.
- To complete her training, she moved to the United States, earning her Ph.D. in Statistics from Ohio State University in 1980. Her doctoral research focused on "ranking and selection" procedures, a field that would later inform her work in biological diagnostics.
Academic Positions:
- In 1981, she joined the Department of Industrial Engineering and Management at Ben-Gurion University of the Negev.
- She remained at BGU for the duration of her career, eventually rising to the rank of Full Professor.
- She also served as the Head of the Department and played a pivotal role in the university’s Faculty of Engineering Sciences.
2. Major Contributions: From Economics to the Gene
Schechtman’s most significant contribution was the adaptation and expansion of the Gini Mean Difference (GMD). While the Gini coefficient was traditionally an economic tool used to measure income inequality, Schechtman recognized its untapped potential as a robust alternative to "variance" in general statistics.
The Gini Methodology (ANOGI):
Alongside collaborator Shlomo Yitzhaki, she developed ANOGI (Analysis of Gini), a counterpart to the traditional ANOVA (Analysis of Variance). This methodology is particularly useful in biology and medicine when data is non-normally distributed or contains outliers—common occurrences in clinical trials and genetic sequencing.
ROC Curve Analysis:
In the realm of medical biology, Schechtman made vital contributions to Receiver Operating Characteristic (ROC) curves. These are used to evaluate the diagnostic power of medical tests (e.g., determining if a biomarker successfully identifies a disease). Her work helped refine how researchers compare the areas under two or more ROC curves, improving the accuracy of clinical diagnoses.
Genetic Mapping:
She applied statistical ranking methods to help biologists identify specific genetic markers associated with complex traits, providing a mathematical framework for "linkage analysis."
3. Notable Publications
Schechtman was a prolific writer, publishing over 100 peer-reviewed papers. Her work appeared in top-tier journals across statistics, medicine, and engineering.
- The Gini Methodology: A Primer on a Statistical Methodology (2013): Co-authored with Shlomo Yitzhaki, this book is considered the definitive text on the subject. It provides a comprehensive framework for using Gini-based statistics in place of traditional methods.
- A Comparison Between the Gini Index and the Coefficient of Variation (1999): Published in Metron, this paper is highly cited for its clarification of when and why the Gini index outperforms standard deviation.
- On Estimating the Area Under a ROC Curve (2004): Published in Statistics in Medicine, this work refined the statistical tools used by clinicians to validate diagnostic tests.
4. Awards & Recognition
Throughout her career, Schechtman was recognized as a leader in the international statistical community.
- Fellow of the American Statistical Association (ASA): This is one of the highest honors in the field, awarded to fewer than one-third of one percent of the ASA membership annually.
- President of the Israel Statistical Association (2007–2009): She served as the head of her national professional body, influencing statistical policy and education in Israel.
- Teaching Excellence: She was a multi-time recipient of the "Best Teacher" award at Ben-Gurion University, reflecting her ability to make complex mathematical concepts accessible to students in biology and engineering.
5. Impact & Legacy
Schechtman’s legacy is defined by methodological pluralism. Before her work, many biologists relied solely on "mean" and "variance"—tools that often fail when data is skewed. By championing the Gini methodology, she gave life scientists a more "robust" toolbox.
Her work continues to influence:
- Bioinformatics: In the analysis of gene expression data.
- Public Health: In measuring health inequalities across different demographic groups.
- Environmental Biology: In assessing biodiversity and species distribution where traditional variance measures are insufficient.
6. Collaborations
Schechtman was known for her interdisciplinary spirit. Her most enduring partnership was with Shlomo Yitzhaki (Hebrew University), with whom she spent decades refining the Gini methodology.
She also collaborated extensively with medical researchers at Soroka Medical Center in Beer-Sheva. These partnerships were crucial in applying her theoretical work to real-world biological problems, such as analyzing the effectiveness of new drug treatments and understanding the epidemiology of regional diseases.
7. Lesser-Known Facts
- Academic Power Couple: Edna was married to Gideon Schechtman, a world-renowned mathematician at the Weizmann Institute of Science specializing in Banach spaces. Together, they represented a formidable force in Israeli mathematics.
- The "Gini" Evangelist: While most people associate the Gini index with "The Rich and the Poor," Schechtman famously argued that it was actually a superior way to look at all data.
She often joked that the Gini index was "the best-kept secret in statistics" and spent her life trying to let the secret out.
- Champion of Women in STEM: As one of the few women in high-ranking positions in Israel's engineering and statistics departments during the 1980s and 90s, she served as an informal mentor to a generation of female Israeli scientists, advocating for rigorous quantitative training as a path to academic leadership.
Edna Schechtman passed away in 2022, leaving behind a body of work that continues to ensure that biological discoveries are grounded in the highest standards of statistical integrity.