Name: Louis Goldwater Christie

Hometown: Waiheke Island, New Zealand

Extracurricular interests: Mountaineering, bouldering, skiing, squash, tennis

Postgraduate degree: PhD in geometric methods in statistics

Life before Catz

"I came to Catz after completing my Masters of Advanced Studies at Trinity College, Cambridge. The Part III Mathematics course is recognised internationally as a hard capstone course that tests you in preparation for postgraduate studies. I really benefitted from the experience; I was able to experience many new areas of mathematics and met many incredible mathematicians from around the world.

"I had graduated with my BSc (Hons) in Mathematics from the University of Auckland in November 2018, but I couldn’t apply – let alone start – the Master’s course at Cambridge until much later in 2019. I seized the opportunity to join a new data analytics team at McGrathNicol in Australia for a brief spell, which gave me an insight into the consulting sector and exposure to a range of interesting projects.

"I was originally inspired to pursue mathematics when I participated in the New Zealand Mathematical Olympiad training programme during high school. It showed me how mathematics is about more than just calculations – it is about the logical structure of problems and how to develop methods to solve them."

Life at Catz

"While my Master’s gave me a footing in Cambridge, it is great to experience another college community which I can call home now! My accommodation is located right next to the Catz sports facilities, which is particularly handy for early morning squash and tennis matches.

"The College’s postgraduate representatives (known as the MCR Committee) and various clubs have ensured there are things to look forward to each week, even during lockdowns. I’ve gotten involved in the circuit training sessions held online by St Catharine’s College Boat Club, and joined in the evening yoga sessions held outdoors on the College sports field. I’m also somewhat of an evangelist for the Catz bouldering club and have already recruited six new members."

Postgraduate studies

"Our world is increasingly built on machine learning tools but we know very little about what is happening under the hood in these models. We would like to know how and why these tools do a good job of identifying patterns that aren’t obvious at first glance, so we can improve the insight that these tools generate in the future.

"My PhD focuses on the use of methods from geometry and group theory in statistical problems, with a view to identifying patterns from which the model can more effectively extrapolate. Many types of data are constrained in some way. In these constrained spaces the usual techniques from linear spaces can produce weird and unusual results because they ignore the geometry, the true special structure, of these spaces. If we can include this information we can often produce more accurate and precise estimates, more powerful statistical tests, and often more insight into the underlying problem. I will be working to understand the statistical properties of some new tools that use this geometric information. These tools have applications in not only in machine learning, but also diverse areas such as neuroimaging and speech analysis."

The Harding Distinguished Postgraduate Scholars Programme

"It was a lovely surprise to be selected for the scholarship and I feel doubly lucky given the longstanding support from St Catharine’s alumnus David Harding (1979, Natural Sciences) for statistics at Cambridge. Other funders are sometimes discipline-specific but the Harding Distinguished Postgraduate Scholars Programme has connected me with 52 scholars across 21 colleges who are studying a variety of subjects. While the independence of PhD studies can be tough – you’re essentially being thrown in the deep end and learning to swim for the first time – I started with connections with other Scholars in the exact same boat so we can all support each other."

Advice for undergraduates thinking of applying for postgraduate studies

"However unlikely opportunities might seem, don’t self-select yourself out of opportunities that you might be interested in simply because you’re worried you might not get them. I was not at all sure whether I would be accepted for my Master’s and PhD courses – I am so glad these initial doubts didn’t hold me back from applying."