Teaching at the college and the university made her known to generations of undergraduates. Her lectures on the contemporary British economy were directed towards the quaintly named paper Economic Organisation, then compulsory for all students reading PPE. College tutorial teaching was, however, the channel through which her influence was most pervasive. The triumphs, including six Firsts out of eight candidates in one notable year, were acknowledged modestly.
At that time the PPE degree at Oxford required all three subjects, philosophy, politics and economics, to be carried through to final examinations. Inevitably not all Somerville undergraduates proved to have a marked aptitude for economics. Hall was never sentimental, but her acerbic comments to colleagues did not conceal her supportive approach and concern to make the subject interesting and accessible to those more comfortable with philosophy or politics.
The mother of two daughters, both undergraduates at Oxford, she ridiculed the in loco parentis approach of colleges which, even in the 1960s, required undergraduates to be back in the college by midnight. A formidable alliance with Enid Starkie, then tutor in French, led to a successful campaign for the introduction of late-gate keys. But her sympathy for student liberties did not extend to the wider student protest movement. As she tartly informed one of her undergraduates who had been involved in a sit-in in university buildings, ``My dear, if breaking and entering is your chosen profession, you should study elsewhere than at Oxford.''
Within economics her own area of specialism was the distributive trades, when the service industries were much less fashionable and well-regarded than now. This drew her into the public policy domain. She was sharply critical of the Selective Employment Tax, the brain-child of Nicholas Kaldor, introduced to assist manufacturing by imposing a differential tax on employment in the service sector. She was an influential advocate of the abolition of resale price maintenance. Yet she was far from being a free-marketeer. One of her favourite phrases, from Professor Joan Robinson, a colleague of J.M. Keynes, was ``competition is about killing off the competition''.
Her expertise in the distributive trades led her to membership of the watchdog Monopolies and Mergers Commission in the 1970s, and to involvement with the Little Neddy for the Distributive Trades within the National Economic Development Office; she set in motion an ambitious review of the sector, with the co-operation of many of the industry's senior figures, who were pleased to feel that its economic importance was at last receiving recognition.
Her first marriage, to Robert Hall (later Lord Roberthall), the government economic adviser, spanned the difficult wartime years. Like many of their contemporaries, they decided to send their children abroad, to his family in Australia. Margaret Hall then found herself unable to return to England, making her way via the west coast of the United States to Washington, where friends found her a job with the Price Commission until the family could be reunited in London at the end of the war. Later, when her husband became Principal of Hertford College, in 1964, she presided with charm and vivacity over college entertaining in the Lodgings - while the college saw to the practical arrangements.
A second marriage, to Sir Donald MacDougall, brought 20 years of happy retirement, in which she took up fishing, although the salmon she promised herself from the Thames was always to elude her.
Laura Margaret Linfoot, economist: born Sheffield 27 August 1910; Fellow and Tutor in Economics, Somerville College, Oxford 1949-75 (Honorary Fellow 1975-95); married 1932 Robert Hall (created 1969 Lord Roberthall, died 1988; two daughters; marriage dissolved 1968), 1977 Donald MacDougall; died London 8 March 1995.