Experimental Design
We collect data from applicant profiles in response to job postings on the online labor marketplace, Upwork. To select the sample for the study, we followed a three-step sampling protocol. First, we chose seven subcategories of job specialization from twelve broad job categories advertised on Upwork. These categories are Admin Support, Data Science & Analytics, Design & Creative, IT & Networking, Translation, Web, Mobile & Software Development, and Writing. Other subcategories, like Sales & Marketing, are not included because of logistic constraints. Second, we look for job postings in each of these subcategories that meet two criteria -- (i) are commonly posted on Upwork, and (ii) are within the range of the research budget. We identify 80 tasks that meet these criteria and prepare our own job posting in a format and language that are similar to those posted on the platform. This is important because we want the jobs that are posted as part of the experiment to resemble other job posts that are regularly seen on the website so that the experimental job posts do not stand out. Third, for each task, we create four job postings that differ only in flexibility to choose work hours within a day and wages. In high-flexibility jobs, freelancers can choose any 2-hour window on a specified date. For low-flexibility jobs, freelancers have to complete the work during a specified two-hour window during the day. The high-wage jobs pay USD $ 40 for the two hours and the low-wage job pays USD $30 for the two hours. Therefore, the four treatment arms of the experiment are:
1. Low wage, low flexibility
2. High wage, low flexibility
3. Low wage, high flexibility
4. High wage, high flexibility
In total, our sample will consist of 320 job postings (80 tasks time 4 postings/task). The experiment will be conducted over the span of four weeks. We will randomly pick one job posting from each of the 80 tasks to be posted in the first week of the experiment. For each of these 80 job postings, we will randomly assign a day of the week to publish the job. The same process will be followed in subsequent weeks for 4 weeks (using sampling without replacement). Job postings will be active for twenty-four hours, and applicant information will be collected at the end of the twenty-four hours. Once a posting is closed, we will randomly hire one of the applicants to complete the assigned job. This candidate will receive the promised payment.