2 research outputs found
Quantitative group testing in the sublinear regime
The quantitative group testing (QGT) problem deals with efficiently
identifying a small number of infected individuals among a large population. To
this end, we can test groups of individuals where each test returns the total
number of infected individuals in the tested pool. For the regime where the
number of infected individuals is sublinear in the total population we derive
the information-theoretic threshold for the minimum number of tests required to
identify the infected individuals with high probability. Such a threshold was
so far only known for the case where the infected individuals are a constant
fraction of the population (Alaoui et al. 2019, Scarlett & Cevher 2017).
Moreover, we propose and analyze an efficient greedy reconstruction algorithm
that outperforms the best known algorithm (Karimi et al. 2019) for certain
sparsity regimes
Quantitative Group Testing and the rank of random matrices
Given a random Bernoulli matrix , an integer and the vector , where is of Hamming
weight , the objective in the {\em Quantitative Group Testing} (QGT)
problem is to recover . This problem is more difficult the smaller is.
For parameter ranges of interest to us, known polynomial time algorithms
require values of that are much larger than .
In this work, we define a seemingly easier problem that we refer to as {\em
Subset Select}. Given the same input as in QGT, the objective in Subset Select
is to return a subset of cardinality , such that for
all , if then . We show that if the square
submatrix of defined by the columns indexed by has nearly full rank,
then from the solution of the Subset Select problem we can recover in
polynomial-time the solution to the QGT problem. We conjecture that for
every polynomial time Subset Select algorithm, the resulting output matrix will
satisfy the desired rank condition. We prove the conjecture for some classes of
algorithms. Using this reduction, we provide some examples of how to improve
known QGT algorithms. Using theoretical analysis and simulations, we
demonstrate that the modified algorithms solve the QGT problem for values of that are smaller than those required for the original algorithms