Quality-assured Synchronized Task Assignment in Crowdsourcing

MPhil Thesis Defence


Title: "Quality-assured Synchronized Task Assignment in Crowdsourcing"

By

Miss Jiayang TU


Abstract

With the rapid development of crowdsourcing platforms that aggregate the 
intelligence of Internet workers, crowdsourcing has been widely utilized 
to address problems that require human cognitive abilities. Considering 
great dynamics of worker arrival and departure, it is of vital importance 
to design a task assignment scheme to adaptively select the most 
beneficial tasks for the available workers. In this thesis, in order to 
make the most efficient utilization of the worker labor and balance the 
accuracy of answers and the overall latency, we a) develop a parameter 
estimation model that assists in estimating worker expertise, question 
easiness and answer confidence; b) propose a quality-assured synchronized 
task assignment scheme that executes in batches and maximizes the number 
of potentially completed questions (MCQ) within each batch. We prove that 
MCQ problem is NP-hard and present two greedy approximation solutions to 
address the problem. The effectiveness and efficiency of the approximation 
solutions are further evaluated through extensive experiments on synthetic 
and real datasets. Our findings from the experiments show that the 
accuracy and the overall latency of the MCQ approaches outperform the 
state-of-the-art online task assignment in the synchronized task 
assignment scenario.


Date:			Monday, 28 May 2018

Time:			2:00pm - 4:00pm

Venue:			Room 2132C
 			Lift 19

Committee Members:	Prof. Lei Chen (Supervisor)
 			Dr. Xiaojuan Ma (Chairperson)
 			Dr. Yangqiu Song


**** ALL are Welcome ****