Checklist 1. For all authors (a)

Another limitation is that the linear model seems to outperform the rank-one quadratic model; we do not fully understand this effect, as discussed in the last paragraph of section 4. A third limitation is that models need to be averaged across time to obtain a single, deployable model: see Figure 5. A final limitation is that we do not yet have convergence theorems or regret bounds for the passive-aggressive updates in these models; see the second paragraph of section 5. (c) Did you discuss any potential negative societal impacts of your work?