With the recognition for his contribution to welfare economics, Sen, 64, master of Trinity College at Cambridge University, becomes the sixth Indian to get the Nobel Prize and the first Asian to merit it for economics. He is also the first solo winner of the prize for economics since 1995.

Announcing the award in Stockholm, the Royal Swedish Academy of Science said Sen was chosen for the honour for his contribution to welfare economics.

``His contributions ranged from axiomatic theory of social choice over definitions of welfare and poverty indices, to empirical studies of famine,'' the citation by the academy said.

Expressing delight over the honour, he told PTI that welfare economics touches the lives of people. With his characteristic humility he noted that many economists had worked on the subjectand ``it is a tragedy we can't all share the award''.

Sen will be presented with a medal and a cheque for 7.6 million Swedish kronor ($938,000) at an official ceremony in Stockholm on December 10, the 102nd death anniversary of founder of the prizes, Alfred Nobel.

Born on November 3, 1933 at Santiniketan founded by another Indian Nobel laureate Rabindranath Tagore, Sen has retained his Indian citizenship despite his long stay abroad as a professor.

He has taught in India and various universities abroad including Harvard, Oxford and London School of Economics.

Sen had been in the reckoning for the Nobel Prize for several years and many of his admirers felt he had been overlooked so far because of his outspoken criticism of the Western model of economic growth, which he felt had fallen short of achieving the welfare of the poor.

His works are notable for a keen interest in how resources are distributed in society, with a focus on the poorest members, the citation said.

Sen's studies on famine inIndia, Bangladesh, Ethiopia and Saharan countries found that shortage of food was not always the cause of such a catastrophy, it said.

``By analysing the available information about different individuals' welfare when collective decisions are made, he has improved the theoretical foundation for comparing different distributions of society's welfare and defined new and more satisfactory indices of poverty,'' the academy said.

``In empirical studies, Sen's applications of his theoretical approach have enhanced our understanding of the economic mechanisms underlying famines,'' the citation said.

Many economists consider Sen as a Left wing professor who however, pursued an independent line of study. From the start of his career Sen showed a ``particular interest in the most impoverished members of society,'' the Swedish academy said.

He was praised by the group of jurors for the prize for his human approach to the dry and detached realm of economic studies. ``By combining tools from economics andphilosophy, he has restored an ethical dimension to the discussion of vital economic problems,'' the citation said.

Author of over a dozen books, Sen's best known works include ``Collective Choice and Social Welfare'' published in 1970 and ``Poverty and Famines'' published in 1981. The latter book challenged the popular notion that the shortage of food was the most important cause of famine and showed that other factors also contributed to it and that the catastrophy could occur even without any significant drop in supplies of food articles.

This is the 30th time that the Nobel Prize is being given for economics. The United States tops the list with most winners, while India, Germany, France, the Netherlands and the former Soviet Union have each won it once.