An Indian scientist and applied statistician, Prasanta Chandra Mahalanobis, known as ‘PCM’ was best remembered for introducing the Mahalanobis distance and being one of the main members of the first Planning Commission of India. Known for his pioneering studies in anthropometry in the country, Mahalabonis was also the founder of the Indian Statistical Institute and contributed largely to the design of sample surveys.
June 29, 2018 is being celebrated as the late statistician’s 125th birthday. Prasanta Chandra Mahalanobis was a Bengali, brought up in Bikrampur, now in Bangladesh. After completing his majors in Physics from Presidency College in Calcutta in 1912, Mahalabonis joined the University of London the following year. It was during his time in London that he was introduced to the journal Biometrika and developed a keen interest in statistics and its utility to problems in meteorology and anthropology.
As Mahalabonis had many colleagues who were interested in statistics, an informal group formed in the Statistical Laboratory located in his room in Presidency college. After calling a meeting with few of his colleagues, Mahalabonis established the Indian Statistical Institute (ISI) and formally registered it on April 28, 1932. Formerly, the Physics department of the college, ISI grew with the pioneering work of some of Mahalabonis’ colleagues and soon the institute founded the journal Sankhya, along the lines of Karl Pearson’s Biometrika.
Mahalabonis Distance (MD) is a multi-dimensional generalisation of the idea of measuring how many standard deviations away is point P from the mean of D. Apart from MD, which measures distance relative to the centroid – a base or central point which can be thought of as an overall mean for multivariate data.
Mahalabonis’ important contributions involved large-scale sample surveys. He introduced the concept of pilot surveys and advocated the utility of sampling methods. During the latter part of his life, Mahalabonis was a part of the Planning Commission of India which was responsible for independent India’s five-year plans, in which he emphasized on the importance of industrialization and also corrected previous census methodology errors. The Planning Commission has now been replaced with the Niti Aayog.
Mahalabonis was deeply interested in cultural pursuits and was awarded one of the highest civilian awards, the Padma Vibhushan from the Government of India for his contribution to science. Mahalabonis died on June 28, 1972, a day before his seventy-ninth birthday.