Our scorecards include both a total score column and a vote index column. You can click on any column to sort by that column. You can use the filter to look at one chamber, one party, or even one specific legislator. If you have set up categories you can see scores calculated for any specific category. You can also click on a legislator to see a summary of their individual scores and the votes that went into them. But what is the difference between the three different scores? Basically, the total score represents impact, the vote index score represents purity, and the possible score is, well, the possible score.
Total Score
For the total score, we take each vote, multiply by the rating you gave the bill, and add up all the results. This resulting score lets you know how much impact a legislator had on your agenda — a combination of how many chances they had to vote, how often they voted correctly, and how they voted on your most important bills.
For bill ratings, bills you support should be given a positive number and bills you oppose should be given a negative number. The larger the absolute value of the number, the more important you feel the bill is. So a bill with a rating of 5 is a bill you support more strongly than a bill with a rating of 3, and a bill with a rating of -2 you oppose a little more strongly than a bill with a rating of -1. Bills you are following and want to be included in the scorecard, but you don’t want to be factored into the scoring, should be given a 0. You decide the rating system. You can use simple -1 and 1, or use a scale of 1 to 5 like movie ratings, 1 to 10 (and -10), or whatever makes sense to you.
To determine if we should add or subtract the bill’s value from the total score we consider if the rating is positive or negative and if the vote was a yes or no. It works exactly like you think it should. If a lawmaker votes for a bill you support or against a bill you oppose, their total score goes up. If they vote for a bill you oppose, or against a bill you support, their total score goes down. The amount it does up or down is controlled by the rating you entered.
Of course, they may be several votes held on any given bill, in one or both chambers. By default, we consider the most recent vote in each chamber. If that is not what you want you can go to the legislation tab, click the edit button next to the bill you want to manage, and scroll to the bottom of the screen. There you will see our tools for managing which votes we include in the score. (more on that here)
You can give legislators extra credit (positive or negative) for sponsoring a bill. You’ll see that option right next to where you set the bill rating. Note we label the Possible Score column Poss Vote Score because we don’t account for the sponsorship bonus points in the possible score. So if you give “extra credit” for sponsoring a bill, you can get legislators with a total score higher than the poss vote score.
Finally, you can also give legislators partial (or full) credit for votes where they are absent. In that case, our calculations give them credit as if they voted the way the majority voted. (more on that here)
Possible Score
The maximum points that a legislator could have gotten, if they voted the “right” way on every bill, is listed in the “Poss Vote Score” column. This value is fairly straightforward. We add up the votes they could have made, just like we would for the total score, but count them as if they had voted correctly. If they were absent or abstained from a specific vote, we still count that vote into their possible score. On the other hand, if they are in the house and the bill was only voted on in the senate, then we don’t consider that as a possible vote, and it doesn’t count in their possible score. Thus members of the house and senate almost always have different possible scores. Likewise in states where we make committee votes available, lawmakers on lots of committees (or committees that hear a lot of your specific bills) will likely have a higher possible score.
Reminder from above: Possible Score “Poss Vote” column does not account for the sponsorship bonus points in the possible score. So if you give “extra credit” for sponsoring a bill, you can get legislators with a total score higher than the poss vote score.
Vote Index
For vote index, the formula is:
Vote Index = (Total Vote Score + Possible Score) / (2*Possible Score)
The formula is basically calculating the percentage of the time the legislator voted correctly, weighted for by your rating. If they vote right every single time the formula gives back 1. If their good votes and bad votes exactly cancel each other out and their total score is 0, and the formula gives .5. And if they vote wrong every time their total score is -possible score, so the formula gives back 0.
But why not just use:
Vote Index = (Total Vote Score) / (Possible Score)
you may ask? Good question! It isn't intuitive but it does make sense if you think through the numbers carefully. Our formula and total/possible would be the same if we only had positive points. But the worst possible score, if they vote wrong on every bill, is -1 * possible. So our formula accounts for the fact the scores are negative but we want the vote index to be positive.
For example, a legislator has a score of 25, and the possible score, if they voted right every time, was 50. It is intuitive to say they get a 50%. But that isn't right, because the worst score isn't 0. A 0 actually means they voted right half the time and wrong half the time. Any positive score indicates they voted right more than 50% of the time.
The number line below shows what I mean. It stretches from -50 to 50. If a legislator scores 25, that is 75% of the way to 50. That matches our formula (total + possible) / 2* possible = (25+50) / 100 = 75%. So their vote index is 75%.
Now think about a legislator with a negative 25 score. That point is 25% of the way to 50. (-25+50) / 2*50 = 25%. So their vote index is 25%, which makes sense. Where as using total/possible, or -25/50, would give an answer that doesn't make sense.
Differences
If you sort lawmakers by their total score, one chamber is likely to be at a disadvantage, but they are on a level playing field when considering the vote index. Also, the difference in the ranking (within a chamber) between the Total Score and the Possible Score matters much more in states where we have committee votes. In those states, a person on the right committee can have a big impact, while still being right a smaller percentage of the time. The difference in ranking can also highlight someone who votes correctly for all the big rating bills and but get some of the small rating bills wrong (or vice versa). Which score is most important to you will depend on your goals, your bills, and the specifics of your state.