I am looking to settle a debate over chart visualization.
My team's UX person has designed multiple charts for displaying data: a bar chart, a line chart, and a dotted line chart. In all the charts, all the series are represented as dots in the legend, regardless of how the series actually looks like in the chart.
I said that the whatever marker is used in the legend, should correspond to the marker used in the actual chart. I.e., if the series is a line, the markers should be lines. If it's a scatter plot with different shapes, it should be the different shapes. So on, so forth.
Which in your opinion is more correct to display?