A Proof of Theoretical Results

A.1 Proof of Lemma 1 The MSE can be computed as E null null ˆ x x null This proves that the estimate (4) is unbiased. A.3 Proof of Theorem 1 The MSE can be computed as E null null ˆ x x null A.5 Proof of Theorem 3 The MSE can be written as E null null ˆ x x null G, by the definition of G. 19 Now using our result in (70) and our inductive assumption we have, E null null null nullw For the purpose of this simulation, we first generate 5 all-(1) vectors and 5 all-(-1) vectors. This is corroborated by our experimental findings in Figure 1. Note that in all cases, data is partitioned equally among all nodes. Rand-k -Temporal significantly outperform other baselines in all settings .