Deco: A System for Declarative Crowdsourcing

Abstract

Deco is a system that enables declarative crowdsourcing: answering SQL queries posed over data gathered from the crowd as well as existing relational data. Deco implements a novel push-pull hybrid execution model in order to support a flexible data model and a precise query semantics, while coping with the combination of latency, monetary cost, and uncertainty of crowdsourcing. We demonstrate Deco using two crowdsourcing platforms: Amazon Mechanical Turk and an in-house platform, to show how Deco provides a convenient means of collecting and querying crowdsourced data.