online decision-making

The Bayesian Prophet: A Low-Regret Framework for Online Decision Making

We develop a new framework for designing online policies given access to an oracle providing statistical information about an offline benchmark. Having access to such prediction oracles enables simple and natural Bayesian selection policies, and …

Ride Sharing

Ridesharing platforms such as Didi, Lyft, Ola and Uber are increasingly important components of the transportation infrastructure. However, our understanding of their design and operations, and their effect on society at large, is not yet well …

Pricing and Optimization in Shared Vehicle Systems: An Approximation Framework

Optimizing shared vehicle systems (bike-sharing/car-sharing/ride-sharing) is more challenging compared to traditional resource allocation settings due to the presence of complex network externalities - changes in the demand/supply at any location …

Online Collaborative-Filtering on Graphs

A common phenomena in modern recommendation systems is the use of feedback from one user to infer the 'value' of an item to other users. This results in an exploration vs. exploitation trade-off, in which items of possibly low value have to be …

Fast Bidirectional Probability Estimation in Markov Models

We develop a new bidirectional algorithm for estimating Markov chain multi-step transition probabilities: given a Markov chain, we want to estimate the probability of hitting a given target state in $\ell$ steps after starting from a given source …

Pricing in Ride-Sharing Platforms: A Queueing-Theoretic Approach

Epidemic Spreading With External Agents

We study epidemic spreading processes in large networks, when the spread is assisted by a small number of external agents: infection sources with bounded spreading power, but whose movement is unrestricted vis-a-vis the underlying network topology. …

FAST-PPR: scaling personalized pagerank estimation for large graphs

We propose a new algorithm, FAST-PPR, for estimating personalized PageRank: given start node $s$ and target node $t$ in a directed graph, and given a threshold $\delta$, FAST-PPR estimates the Personalized PageRank $\pi_s(t)$ from $s$ to $t$, …

The behavior of epidemics under bounded susceptibility

We investigate the sensitivity of epidemic behavior to a bounded susceptibility constraint -- susceptible nodes are infected by their neighbors via the regular SI/SIS dynamics, but subject to a cap on the infection rate. Such a constraint is …

Greedy Sensor Selection under Channel Uncertainty

Estimation in resource constrained sensor networks where the fusion center selects a fixed-size subset from a pool of available sensors observing the states of a linear dynamical system is considered. With some probability, the communication between …