I've struggled and gone back and forth on that, and it's somewhat arbitrary -- compared to the obvious up-down orientation for signal/noise votes. The fact that questionnaires and poll-charts are more likely to put 'yes/agree' on the left and 'no/disagree' on the right swayed my proposed orientation, but I could be flipped.
I also think rather than just a net tally, results could be shown as a teeny tiny inline horizontally stacked barchart -- a sparkline of sorts -- with the overhang of the leading sentiment in its vote-direction. For example, with left-agrees, this would be more agrees than disagrees:
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More disagrees than agrees:
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But this sort of display might argue for right-agrees; number-lines and cartesian axes go positive to the right, and right-motion in some way signals acquiescence/continuation in the direction of the reviewed text.
I also think rather than just a net tally, results could be shown as a teeny tiny inline horizontally stacked barchart -- a sparkline of sorts -- with the overhang of the leading sentiment in its vote-direction. For example, with left-agrees, this would be more agrees than disagrees:
More disagrees than agrees: But this sort of display might argue for right-agrees; number-lines and cartesian axes go positive to the right, and right-motion in some way signals acquiescence/continuation in the direction of the reviewed text.