Analysis of Networks via the Sparse β-Model
- 👤 Speaker: Chenlei Leng, University of Warwick
- 📅 Date & Time: Friday 01 March 2019, 16:00 - 17:00
- 📍 Venue: MR12
Abstract
We propose the Sparse β-Model, a new network model that interpolates the celebrated Erdos-Renyi model and the more recent β-model that assigns one different parameter to each node. By a novel reparametrization of the β-model to distinguish global and local sparseness and assuming that many parameters therein are zero, our model can drastically reduce the dimensionality of the β-model. For estimating its parameters, we formulate a penalized likelihood approach with the l_0 penalty. Remarkably, we show via a monotonicity lemma that the seemingly combinatorial computational problem due to the l_0 penalty can be overcome by assigning nonzero parameters to those nodes with the largest degrees. We show further that a β-min condition guarantees our method to identify the true model and provide excess risk bounds for the estimated parameters. The estimation procedure enjoys good finite sample properties as shown by simulation study. The usefulness of our model is further illustrated via the analysis of a microfinance take up example.
Series This talk is part of the Statistics series.
Included in Lists
- All CMS events
- All Talks (aka the CURE list)
- bld31
- Cambridge Forum of Science and Humanities
- Cambridge Language Sciences
- Cambridge talks
- Chris Davis' list
- CMS Events
- custom
- DPMMS info aggregator
- DPMMS lists
- DPMMS Lists
- Guy Emerson's list
- Hanchen DaDaDash
- Interested Talks
- Machine Learning
- MR12
- rp587
- School of Physical Sciences
- Statistical Laboratory info aggregator
- Statistics
- Statistics Group
Note: Ex-directory lists are not shown.
![[Talks.cam]](/static/images/talkslogosmall.gif)

Chenlei Leng, University of Warwick
Friday 01 March 2019, 16:00-17:00