Spencer Frei

Department of Statistics
University of California, Los Angeles

Email: spencerfrei@ucla.edu
photo

I am a PhD candidate in the Statistics department at UCLA and a member of the Statistical Machine Learning Lab led by Quanquan Gu. I also develop the deep learning algorithms that power the Chatterbaby app.

Research Interests

* Theory of deep learning: optimization, generalization, etc.
* Statistical learning theory
* Non-convex optimization
* Applications of deep learning: natural language understanding, audio analysis, etc.

Recent news

2020
* New paper on agnostic learning of halfspaces using gradient descent is now on arXiv.
* My single neuron paper was accepted at NeurIPS 2020.
* I received a Best Reviewer Award for ICML 2020.
* I will be attending the IDEAL Special Quarter on the Theory of Deep Learning hosted by TTIC/Northwestern for the fall quarter.
* I'm reviewing for AISTATS 2021.
* Updated the arXiv version of my recent paper on agnostic learning of a single neuron with improved bounds.
* I've been awarded a Dissertation Year Fellowship by UCLA's Graduate Division.
* New paper on agnostic PAC learning of a single neuron using gradient descent is now on arXiv.
* New paper accepted at Brain Structure and Function from work with researchers at UCLA School of Medicine.
* I'll be (remotely) working at Amazon's Alexa AI group for the summer as a research intern, working on natural language understanding.
* I'm reviewing for NeurIPS 2020.
* I'm reviewing for ICML 2020.

2019
* My paper with Yuan Cao and Quanquan Gu, "Algorithm-dependent Generalization Bounds for Overparameterized Deep Residual Networks", was accepted at NeurIPS 2019 (arXiv version, NeurIPS version).

I am currently a PhD candidate in the Statistics department at UCLA and a member of the Statistical Machine Learning Lab.  I am supervised by Ying Nian Wu from the Department of Statistics and Quanquan Gu from the Department of Computer Science. I completed my masters in mathematics at the University of British Columbia, Vancouver, in May 2015.  I was a member of the Probability Group, and Ed Perkins was my supervisor.  Before that, I completed my undergraduate degree in mathematics at McGill University in 2013.

You may find more information about me on my CV (last updated August 2020).

For 2020-2021, I have a UCLA Dissertation Year Fellowship and will not be teaching.

Past teaching positions:
Spring 2020: Stats 100C, Linear Models with Arash Amini.
Fall 2019: Stats 102C, Monte Carlo Methods with Qing Zhou.
Summer 2016, Session C: Stats 10, Intro Statistics with Juana Sanchez.
Summer 2016, Session A: Stats 10, Intro Statistics with Miles Chen.
Fall 2016: Stats 100A, Introduction to Probability Theory with Ying Nian Wu.
Winter 2016: Stats 100B, Introduction to Mathematical Statistics with Jessica Li.

Since Fall 2017, I have been working as a graduate student researcher (GSR) for Ariana Anderson at the Semel Institute for Neuroscience and Human Behavior. For the 2016-2017 school year, I worked as a GSR for Ariana Anderson and Monika Mellem.

Preprints

1. S. Frei, Y. Cao, and Q. Gu. Agnostic learning of halfspaces with gradient descent via soft margins. Preprint, arXiv:2010.00539. [arxiv]

Refereed Conference Publications

2. S. Frei, Y. Cao, and Q. Gu. Agnostic learning of a single neuron with gradient descent. In Neural Information Processing Systems (NeurIPS), 2020. [arxiv]

3. S. Frei, Y. Cao, and Q. Gu. Algorithm-dependent generalization bounds for overparameterized deep residual networks. In Neural Information Processing Systems (NeurIPS), 2019. [arxiv], [camera ready]

Journal Publications

4. A.E. Anderson, M. Diaz-Santos, S. Frei et al. Hemodynamic latency is associated with reduced intelligence across the lifespan: an fMRI DCM study of aging, cerebrovascular integrity, and cognitive ability. Brain Structure and Function, 2020. [link]

5. S. Frei and E. Perkins. A lower bound for $p_c$ in range-$R$ bond percolation in two and three dimensions. Electronic Journal of Probability 21(56), 2016. [link]

6. S. Frei, K. Lockwood, G. Stewart, J. Boyer, and B.S. Tilley. On thermal resistance in concentric residential geothermal heat exchangers. Journal of Engineering Mathematics 86(1), 2014. [link]