1. A method for result aggregation in a crowdsourcing environment, the method comprising: providing a task with a plurality of solution options and a range of confidence values corresponding to the plurality of solution options to multiple workers; receiving responses for the task from the multiple workers, wherein each of the responses comprises at least a worker's selection of one of the plurality of solution options and a worker response confidence value selected from the range of confidence values corresponding to the selected one of the plurality of solution options, and wherein the worker response confidence value is indicative of confidence of a worker for the one of the plurality of solution options to be correct; estimating a task answer for the task based on at least the worker response confidence value received from each of the multiple workers; and computing a performance bonus for each of the multiple workers based on the task answer, the worker response confidence value in the response from each worker, and a Proper Scoring Rule.