Logic expert receives top science prize

Professor Rod Downey grapples with some of the most mind-boggling science there is — how dense mathematical processes can be, or can’t be, packed into algorithms for computers to use. For the rest of us, he likens it to baking.

“A good cake recipe would be one that makes a good cake,” explained the internationally recognised Victoria University logician, who has just received New Zealand’s highest science honour, the Rutherford Medal. “Mathematically a good algorithm would be one that uses less resources, runs faster and uses less memory.”

And his work hasn’t just been confined to faculty whiteboards or syllabuses.

It’s been applied to efforts as varied as studying Aboriginal children in Australia, reconstructing the “tree of life”, understanding the evolution of European languages, and even designing better ways to distribute donated food to charities.

That came from a field of algorithm design he founded with computer scientist Professor Michael Fellows, called parameterised complexity.

It generally showed that many apparently intractable computations could become feasible once fixed values were given to certain parameters, such as the amount of input data to be used or the size of object to be computed.

This subject is now an important new branch of theoretical computer science, with its own international conferences, books and special issues of journals.

Another of his specialist fields is “algorithmic randomness” — something which could help pick one piece of DNA apart from another, or tell if one composer plagiarised another.

The medal, awarded by Royal Society Te Apa¯rangi, recognised his outstanding contribution to science, along with his record as a research leader and mentor.

Downey said he was “honoured and somewhat startled” to receive it.

Others recognised at the society’s Research Honours Dinner this year included Professor Linda Tuhiwai Smith who received the inaugural Te Pua¯waitanga Award for her contributions to Te Ao Ma¯ori and indigenous knowledge.

Another new award, Te Tohu Rapuora, was presented by the Health Research Council of New Zealand to the University of Waikato’s Te Kotahi Research Institute.

The council also presented its Lily Medal to clinician and University of Auckland researcher Professor Cynthia Farquhar, whose recent trial into intrauterine insemination showed for the first time what benefits the fertility treatment could bring.