In visual inference, the decision is made based on human feedbacks on specific plot called lineup. The question is, whether a person can become skillful over time on certain lineup and provide more accurate feedback than others who are not acquainted with that type of plot or data graphics in general. To understand this learning trend on lineup, several experiments were conducted with human subjects. Data on human demographics, their educational background and geographical location were also collected. In this presentation we talk about the interesting findings from these experimental data.