MELBOURNE, TUESDAY 10 FEBRUARY 2015: Would you call a food blogger an expert? In the eyes of some mathematical algorithms that is exactly what they are.
Online restaurant reviews are a way of seeing group decision making in action: Hundreds and thousands of diners rate a restaurant, the ratings are summed together to give a single rating, but how do these sites stop average restaurants from inflating their rating?
Laura Smith has spent her summer researching how mathematics can help ensure minorities cannot skew ratings.
“Say you have a group of four food bloggers who want to rank three restaurants. Three agree and vote restaurant a the top restaurant, followed by restaurant c then b. However, the fourth is bribed by restaurant c, so gives restaurant c a really high score to increase c’s average and a a really low score to decrease a’s average,” Laura explains.
“The algorithms we have been looking at can identify and remedy these biases, giving a more accurate view of the majority. In this case the fourth blogger’s scores will be given a lower weighting in the overall scores as they differ greatly from the others, hopefully resulting in a fair result: a being voted top restaurant,” she says.
While this may seem like a low impact application the same technique is used widely throughout the business sector. Financial institutions, government bodies, large boards — just to name a few — use the technique to manage risk and make decisions where a group of experts each contribute an opinion.
Laura’s project is one of 56 student projects sponsored by the Australian Mathematical Sciences Institute (AMSI) through their Vacation Research Scholarship program (VRS).
Over the past eleven years 428 students have taken part in the program. Dr Simon James, Laura’s supervisor, was a VRS student himself. He gives an insightful view into the program: “VRS gave me the confidence to believe I could pursue mathematics as a career; all of a sudden I was being paid to do mathematics.” Simon also said the program encourages students to continue their studies as it gives them a taste of the research world.
And Laura agrees: “For me, the VRS has been a way of experiencing research and the academic world, while being paid and without a 12 month commitment!” Laura says. “I have tackled an interesting problem under the guidance of a supervisor. I now have an idea of what to expect from post-graduate studies in mathematics and the impact the research can have.”
Professor Geoff Prince, AMSI Director, says: “Thanks to co-funding from the Department of Education and Training the Vacation Research Scholarships allow young mathematicians to dedicate their time to understanding a specific topic. And it sends them the message that they and their skills are valuable. It is an essential program to safeguard Australia’s future supply of researchers with expertise in the mathematical sciences.”
Hear Laura and other VRS students present their research at the Big Day In hosted by AMSI.
Big Day In:
11-12 February 2015
Trinity College, The University of Melbourne