{"id":17317,"date":"2026-06-29T17:14:59","date_gmt":"2026-06-29T17:14:59","guid":{"rendered":"https:\/\/www.smilefoundationindia.org\/blog\/?p=17317"},"modified":"2026-06-29T17:20:33","modified_gmt":"2026-06-29T17:20:33","slug":"national-statistics-day-2","status":"publish","type":"post","link":"https:\/\/www.smilefoundationindia.org\/blog\/national-statistics-day-2\/","title":{"rendered":"National Statistics Day: Why P.C. Mahalanobis still shapes India&#8217;s data revolution\u00a0"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\"><strong>Summary<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>National Statistics Day honours P.C. Mahalanobis, the statistician who laid the foundations of evidence-based policymaking in India.<\/li>\n\n\n\n<li>Mahalanobis introduced scientific sampling methods that transformed how governments collect and use data.<\/li>\n\n\n\n<li>Institutions such as the Indian Statistical Institute and the National Sample Survey remain central to India&#8217;s statistical ecosystem.<\/li>\n\n\n\n<li>His Mahalanobis Distance continues to power applications in AI, machine learning, fraud detection and medical diagnostics.<\/li>\n\n\n\n<li>His work highlights the importance of representative, unbiased data for ethical artificial intelligence and better policymaking.<\/li>\n\n\n\n<li>As STEM becomes increasingly data-driven, Mahalanobis&#8217;s legacy reminds us that meaningful progress depends on asking the right questions of data.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"682\" src=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-1024x682.jpg\" alt=\"National Statistics Day\" class=\"wp-image-17320\" srcset=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-1024x682.jpg 1024w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-300x200.jpg 300w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-768x512.jpg 768w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-1536x1023.jpg 1536w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429-1200x800.jpg 1200w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1780922136429.jpg 1600w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>Our lives are governed by numbers. Whether it is running a household, a business, a city or an entire country, decisions rely on data. It is through surveys, censuses and statistical studies that governments and institutions understand the needs of millions and make decisions that affect them. How many children are enrolled in school? Which districts face the highest rates of malnutrition? How many households have access to clean drinking water? Behind every welfare scheme, public health campaign or development programme lies a vast body of data, all collected to answer one deceptively simple question: How do we know?&nbsp;<\/p>\n\n\n\n<p>For India, the answer to that question owes much to one man. Prasanta Chandra Mahalanobis, scientist and statistician, who transformed statistics from an academic discipline into a practical tool for governance. His pioneering work on sampling and data collection helped governments understand the realities of a vast and diverse country, laying the foundations of evidence-based policymaking that continue to shape India today.&nbsp;<\/p>\n\n\n\n<p>Today, <a href=\"https:\/\/www.forbes.com\/sites\/bernardmarr\/2023\/07\/12\/unleash-the-power-of-data-transforming-business-models-for-tomorrows-market\/\" rel=\"nofollow noopener\" target=\"_blank\">data<\/a> has gone on to become the language through which societies understand themselves. Governments rely on statistics to allocate resources, researchers use datasets to uncover patterns, companies train artificial intelligence models on vast quantities of information\u2014the process is almost inexcusable.&nbsp;<\/p>\n\n\n\n<p>Observed every year on June 29, National Statistics Day commemorates Mahalanobis&#8217;s birth anniversary. While he is widely remembered for the statistical distance that bears his name, his greatest contribution may have been far more ambitious: convincing a newly independent nation that sound policy begins with sound evidence.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>National Statistics Day: Building a Nation Through Numbers&nbsp;<\/strong><\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-1024x683.jpg\" alt=\"Woman carrying child, doctor consulting nearby\" class=\"wp-image-17321\" srcset=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-1024x683.jpg 1024w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-300x200.jpg 300w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-768x512.jpg 768w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-1536x1024.jpg 1536w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1-1200x800.jpg 1200w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1781238518489-1-1.jpg 1600w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>When India gained Independence in 1947, it inherited enormous developmental challenges. Policymakers needed reliable information on agriculture, employment, health, education, industrial production and household consumption. Yet comprehensive administrative data were scarce, making informed planning exceedingly difficult. Imagine trying to plan for hundreds of millions of people without knowing how many children attend school, where crops are failing or which communities lack access to healthcare. That was the challenge confronting India&#8217;s leaders in the years after Independence.&nbsp;<\/p>\n\n\n\n<p>Before they could solve the country&#8217;s problems, they first had to measure them.&nbsp;<\/p>\n\n\n\n<p>Mahalanobis, a physicist by training but a statistician by instinct, understood that governing a country as vast and diverse as India required more than intuition or isolated observations. It demanded systematic, scientifically collected evidence. Long before evidence-based policymaking became a global development mantra, he championed statistical thinking as the foundation of public policy.&nbsp;<\/p>\n\n\n\n<p>This philosophy shaped some of independent India&#8217;s most enduring institutions. The Indian Statistical Institute (ISI) in Kolkata, founded by Mahalanobis in 1931, evolved into a globally recognised centre for statistical research. Equally transformative was the <a href=\"https:\/\/www.mospi.gov.in\/national-sample-survey-office\" rel=\"nofollow noopener\" target=\"_blank\">National Sample Survey (NSS)<\/a>, which pioneered the use of large-scale sample surveys as a practical alternative to complete enumeration. Instead of attempting the impossible task of measuring every household, carefully designed sampling techniques generated reliable national estimates while dramatically reducing cost and time.\u00a0<\/p>\n\n\n\n<p>The innovation proved revolutionary.&nbsp;<\/p>\n\n\n\n<p>Today, sample surveys remain central to labour force studies, health assessments, agricultural statistics, consumption expenditure surveys and several other development programmes across the world. In many ways, Mahalanobis demonstrated that the quality of evidence depends not on collecting the most data, but on <a href=\"https:\/\/www.bbc.com\/news\/world-asia-india-61870699\" rel=\"nofollow noopener\" target=\"_blank\">collecting the right data<\/a>.\u00a0<\/p>\n\n\n\n<p>His influence also extended beyond statistical methodology. As an architect of India&#8217;s early planning process, Mahalanobis advocated for using quantitative models to guide investment, industrialisation and resource allocation. Although aspects of his economic planning framework continue to be debated, his broader principle that complex national decisions should be grounded in rigorous empirical evidence rather than political instinct alone has endured.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>From Statistical Thinking to the Age of AI&nbsp;<\/strong><\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"1024\" height=\"682\" src=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-1024x682.jpg\" alt=\"Smiling woman and boy together outdoors\" class=\"wp-image-17322\" srcset=\"https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-1024x682.jpg 1024w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-300x200.jpg 300w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-768x512.jpg 768w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-1536x1023.jpg 1536w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1-1200x800.jpg 1200w, https:\/\/www.smilefoundationindia.org\/blog\/wp-content\/uploads\/2026\/06\/1782564580909-1.jpg 1600w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>Mahalanobis&#8217;s legacy has become even more relevant in an era defined by <a href=\"https:\/\/www.thehindu.com\/todays-paper\/tp-opinion\/mahalanobis-in-the-era-of-big-data-and-ai\/article67021426.ece\" rel=\"nofollow noopener\" target=\"_blank\">artificial intelligence and big data<\/a>. While today&#8217;s technologies can process information at unprecedented speed, they remain fundamentally dependent on the quality of the data they receive. A flawed dataset can produce misleading predictions just as easily as a flawed survey can distort public policy. This is where Mahalanobis&#8217;s emphasis on representative sampling and rigorous statistical reasoning acquires renewed significance.\u00a0<\/p>\n\n\n\n<p>His influence is also embedded in modern data science through the Mahalanobis distance, a statistical measure he introduced in 1936 to determine how similar or different a data point is from a larger dataset. Unlike conventional distance measures, it accounts for relationships between variables, making it especially effective for analysing multidimensional data. Today, it is widely used in machine learning for anomaly detection, pattern recognition, image processing, fraud detection and medical diagnostics, demonstrating how a concept developed nearly a century ago continues to underpin some of today&#8217;s most sophisticated AI systems.<\/p>\n\n\n\n<p>At the same time, Mahalanobis&#8217;s work offers valuable lessons for contemporary debates around algorithmic bias and ethical artificial intelligence. Machine learning models often inherit biases embedded in historical datasets, leading to unequal outcomes across gender, caste, geography or income groups. Addressing these challenges requires more than just computational expertise; but one needs statistical literacy and an understanding of how data are collected, sampled and interpreted. The question is no longer simply whether an algorithm is accurate, but whether the data used to train it adequately represent the society it seeks to model.&nbsp;<\/p>\n\n\n\n<p>This convergence of statistics, computing, and the social sciences has indeed transformed STEM <a href=\"https:\/\/www.smilefoundationindia.org\/education\">education<\/a> too, because across AI, epidemiology, climate science, students are expected to analyse data, interpret evidence and solve real-world problems using statistical methods. Mahalanobis\u2019s contribution is integral to such statistical thinking because he, in his practice, integrated statistics with economics, agriculture, planning, demography and public policy, making it inherently interdisciplinary.&nbsp;<\/p>\n\n\n\n<p>In this way, National Statistics Day can be believed to be more than a commemoration of one pioneering scholar. It happens to be an opportunity to recognise that numbers, when gathered responsibly and interpreted thoughtfully, are among the most powerful instruments for solving real-world problems. Nearly a century after Mahalanobis laid the foundations of modern statistical thinking in India, his central insight remains remarkably relevant: progress is not driven by data alone, but by our ability to ask meaningful questions of it.&nbsp;<\/p>\n\n\n\n<p>In a world increasingly defined by artificial intelligence and digital technologies, that lesson may be more important than ever.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>FAQs: National Statistics Day<\/strong><\/h3>\n\n\n\n<p><strong>1. Why is National Statistics Day celebrated in India?<\/strong><br>National Statistics Day commemorates the birth anniversary of P.C. Mahalanobis and recognises his contributions to statistics and national development.<\/p>\n\n\n\n<p><strong>2. Who was P.C. Mahalanobis?<\/strong><br>He was an Indian statistician who pioneered modern sampling techniques and helped establish evidence-based policymaking in India.<\/p>\n\n\n\n<p><strong>3. What is the Mahalanobis Distance?<\/strong><br>It is a statistical measure used to determine how different a data point is from a dataset, widely applied in AI, machine learning and medical research.<\/p>\n\n\n\n<p><strong>4. Why is Mahalanobis important in the age of AI?<\/strong><br>His emphasis on representative data and rigorous statistical methods remains essential for building accurate, fair and unbiased AI systems.<\/p>\n\n\n\n<p><strong>5. What is the National Sample Survey (NSS)?<\/strong><br>The NSS is India&#8217;s large-scale survey system that uses scientific sampling to generate reliable national statistics on employment, health, consumption and other development indicators.<\/p>\n\n\n\n<p><strong>6. Why is statistical literacy important today?<\/strong><br>Statistical literacy helps individuals and institutions interpret evidence, identify bias and make informed decisions in an increasingly data-driven world.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On National Statistics Day, explore the enduring legacy of P.C. Mahalanobis, whose pioneering work transformed statistics into a cornerstone of public policy. From India&#8217;s planning process to artificial intelligence and data science, his ideas continue to shape how governments, researchers and institutions make evidence-based decisions in an increasingly data-driven world.<\/p>\n","protected":false},"author":1,"featured_media":17319,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,10],"tags":[],"class_list":["post-17317","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-in-the-spotlight","category-insights"],"_links":{"self":[{"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/posts\/17317","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/comments?post=17317"}],"version-history":[{"count":3,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/posts\/17317\/revisions"}],"predecessor-version":[{"id":17324,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/posts\/17317\/revisions\/17324"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/media\/17319"}],"wp:attachment":[{"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/media?parent=17317"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/categories?post=17317"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.smilefoundationindia.org\/blog\/wp-json\/wp\/v2\/tags?post=17317"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}