Prof Prasanta Chandra Mahalanobis, the father of Indian Statistics, will always be remembered for his contribution to the Indian Statistical System and the discipline of statistics. He was born on June 29, 1893, in a traditional Bengali family at Cornwallis Street, Calcutta. His father, Probodh Chandra Mahalanobis was a businessman and dealer of gramophones and sport goods; he was instrumental in the first successful recording of Rabindranath Tagore’s voice in 1924. His mother, Nirodbasini Devi was a housewife. He was the eldest among two brothers and four sisters. His ancestors were from Panchasar village, now in Bikrampur, Bangladesh and used the family name ‘Bandyopadhaya’.
His great grandfather, Gurucharan Bandyopadhaya was an official who kept the land and revenue accounts of the Mahal of ancient Bengal. People holding such responsibility were initially known as “Nauvice” (or Munshi), accordingly they adopted the title of Mahalanobis which subsequently became the family surname.Young Prasanta graduated with honours in physics from Presidency College, Calcutta, in 1912. He went to England in 1913 to study BSc at the University of London. While waiting for the course to begin, he made a trip to Cambridge where he was impressed by the King’s College campus. He, by chance, missed the train back to London and stayed the night with a friend.
There, he met a student of King’s College who suggested him to apply to study there. Remarkably, he was interviewed the next day and got admission to the King’s College. He passed Part I of the mathematical tripos (honours examination for a graduate degree at Cambridge University) in 1914. He then transferred to the natural sciences, and obtained a first class in Part II in 1915. He was awarded a Senior Scholarship by King’s College. With his specialisation in physics, he set up a research project at the Cavendish Laboratory.
Mahalanobis returned to India in July 1915 to take a short holiday before beginning his research project. However, he was to wait in Cambridge for the boat journey to India. The boat was delayed due to World War I and Mahalanobis spent this time in the library of King’s College. There he looked at some volumes of Biometrika (a journal of statistics published by Oxford University Press) and, being fascinated by what he read, bought a complete set of volumes and took them back to India with him. Reading those books while on his journey, and even after reaching Calcutta, he visualised statistics as a new science connected with measurements and their analysis and had wide application.
On his eventual return to India, Mahalanobis started teaching physics at the Presidency College and was elevated to the rank of professor in 1922. Throughout, he continued his engagement with statistics. He found some interesting problems in meteorology, anthropology and biology, and started working on them. He set up an unofficial group working on statistical problems in Presidency College. It soon acquired the name of the Statistical Laboratory and was located in Mahalanobis’s room in the Physics Department.
His interest in statistics soon evolved into a serious academic pursuit. For instance, in 1920, when he was attending the Indian Science Congress in Nagpur, he was approached by the Director of the Zoological Survey of India asking him whether he would be interested in looking at the data related to mixed race people in Calcutta. Mahalanobis was, indeed, interested, and his analysis of the data led to his first scientific paper, Anthropological observations on the Anglo-Indians of Calcutta – Analysis of male stature (1922). It was noteworthy work and for this, and several other similar researches, he introduced the D2 statistic, known today as the ‘Mahalanobis distance’. It came to be widely referred and used by a large number of researche\s and is taught as part of a regular statistics course.
Seeing the use of Mahalanobis’s anthropological paper, the Director General of Observatories invited him to examine some meteorology problems. Mahalanobis got the data analysed and brought out three important publications: (1) On the seat of activity in the upper air (1923); (2) On errors of observation and upper air relationships (1923); and (3) Correlation of upper air variables (1923). He also published a statistical note on the significant character of local variation in proportion of dextral and sinistral shells in samples of the snail in 1923.
On December 17, 1931, Mahalanobis and professors of economics and applied mathematics at Presidency College passed a resolution to set up the Indian Statistical Institute. It was formally registered on April 28, 1932 as a non-profit distributing learned society under the Societies Registration Act XXI of 1860. It started training courses in statistics. In 1948, the institute received a major grant from the Government of India allowing them to set up a Research and Training School and appoint professors, assistant professors and other academic grades.
Under Mahalanobis’s leadership, the institute flourished. In 1950, it purchased about four acres of land at BT Road, Calcutta and constructed the main building which was inaugurated by RA Fisher (father of statistics) in 1951. The Research and Training School subsequently moved to this building. In 1959, the Government of India passed the resolution (the 57th Act of 1959) declaring the Indian Statistical Institute as the Institute of National Importance.
Mahalanobis introduced innovative techniques for conducting large-scale sample surveys and calculated acreages and crop yields by using the method of random sampling. He devised a statistical method called fractile graphical analysis, which was extensively used to compare the socioeconomic conditions of different groups of people. He applied statistics to disaster management for flood control. With his outstanding contributions in various areas including agriculture, economic planning, natural disaster management — particularly in the field of flood and famine — industrialisation strategies, sampling etc. Mahalanobis was appointed as the honorary statistical adviser to the Government of India in 1949. He served on various national and international committees including the chairman of the United Nations Sub Commission on Sampling from 1947-51. We call him the Father of the Statistical System for his multi-faceted contributions. He established the National Sample Survey (NSS) in 1950 providing comprehensive socioeconomic statistics in India. He set up the Central Statistical Organisation (CSO) which has recently been renamed as National Statistical Office (NSO). Both, the NSS and NSO are now two wings of the Government of India’s Ministry of Statistics & Programme Implementation (MoSPI), to serve as statistical agencies for government’s data collection and coordination of statistical activities in India.
Mahalanobis was a member of the Planning Commission of India from 1955-1967 for its Second Five-Year Plan. The plan encouraged the development of heavy industry in India. It was based on the Mahalanobis’s mathematical description of the Indian economy, which was later known as the Mahalanobis model. For his pioneering work and contributions to the society, he was awarded the Padma Vibhushan, the second highest civilian honour, by the Government of India in 1968.
Mahalanobis also founded Sankhyā (the Indian journal of statistics) emphasising that the spirit and outlook of the journal be universal with the special needs of India without restricting the scope of the journal for the development of statistical methods for varying situations.
When Mahalanobis passed away on June 28, 1972, a day before his 79th birthday, he was still active doing his research work, looking after the Indian Statistical Institute as Honorary Secretary and Director and helping the government as Honorary Statistical Adviser. Dr C R Rao, one of the most renowned living statisticians who trained under him, said: “Mahalanobis Era in statistics, which started in the early twenties, has ended. It will be remembered for all time to come as the golden period of statistics in India, marked by intensive development of a new technology and its applications for the welfare of mankind.”
The MoSPI has instituted an international and three national awards in statistics in the memory of Prof P C Mahalanobis. The international award is given to a statistician of a developing country for lifetime contribution. The national award is given for outstanding work in Official Statistics in order to promote excellence and recognise outstanding contributions made by Official Statisticians in the area of Official/Administrative Statistics in India for category ‘A’ (for those under age 45), category ‘B’ (above 45 years of age) and category ‘C’ (above 55 years of age).
June 29, the birth anniversary of Prof P C Mahalanobis, is celebrated as India’s National Statistics Day to create awareness about the role of statistics in socio-economic planning and policy formulation. On this day, besides the above three national awards mentioned, two other awards are conferred, namely, Prof PV Sukhatme Memorial National Award for lifetime achievement in Statistics and Prof CR Rao award to a young statistician for outstanding contribution in statistics, every alternate year by the MoSPI.
