1. A method of job scheduling in a computing environment, comprising: collecting historical job data related to job submissions received from a plurality of users, the historical job data related to a job submission received from a user comprising: resource request data indicative of resources requested by the user for executing a job, and resource usage data indicative of actual resources used to execute the job; calculating a believability score for each of the plurality of users based on a comparison between the job resource request data and the resource usage data related to one or more job submissions received from the user, the believability score indicating a degree to which the user overestimates resources required to execute jobs; receiving a new job submission from the user of the plurality users, the new job submission specifying a new job to be executed and resources requested by the user for executing the new job; and scheduling the new job for execution based on the believability score of the user.