The “Issues and Leaders” model, developed by PollyVote member Andreas Graefe, predicts the national popular vote from people’s perceptions of the candidates’ issue-handling competence and their leadership qualities. The model demonstrates that the direct influence of party identification on vote choice decreases over the course of the campaign, whereas issues gain importance. The model has decision-making implications in that it advises candidates to engage in agenda setting and to increase their perceived issue-handling and leadership competence.
Variables and data
The model uses two variables, one to capture the candidates’ issue-handling competence and one to capture their expected performance as leaders. Data are collected from polls.
The model assumes that voters favor the candidate that they expect to do the better on handling important issues. Three conditions have to be met for an issue to influence vote choice: (1) the voter is aware of the issue, (2) the issue is of some importance to him, and (3) he expects one party to do a better job in handling the issue than the other parties.
These conditions have been operationalized by collecting data from two types of polls:
- Issue-salience polls, which ask people which issue they regard as most important, such as ‘‘What do you think is the most important problem facing this country today?’’
- Issue-handling polls, which ask people which candidate / party will do the better job in handling that issue, such as “Regardless of which (2016) presidential (election) candidate you support, please tell me if you think Hillary Clinton or Donald Trump would better handle each of the following issues. How about..
The model further assumes that elections are choices between candidates and that candidates’ leadership evaluations are an important determinant of people’s vote choice. Therefore, the model uses information from polls that ask people who they think would be the better leader, such as: “Regardless of how you intend to vote, who do you think is a stronger leader: Hillary Clinton or Donald Trump?’’
The model’s vote equation reads as:
V= P + b
I + c
I represents the issues score and
L the leadership score, measured t days before Election Day. The dependent variable V refers to the incumbent’s actual share of the two-party popular vote.
With its first appearance in 2012, the model provided accurate forecasts. Furthermore, an ex post analysis across the past five elections shows that the model’s ex ante forecasts, calculated three to two months prior to Election Day, were competitive with those from the best of eight established political economy models. Model accuracy substantially improved closer to Election Day. The final Election Eve forecasts missed the actual vote shares by, on average, little more than one percentage point and thus reduced the error of the Gallup pre-election poll by 30%.
- Graefe, A. (2016). Issue-handling beats leadership: Issues and Leaders model predicts Clinton will defeat Trump. Research & Politics, https://doi.org/10.1177/2053168016679364 .
- Graefe, A. (2013). Issue and leader voting in U.S. presidential elections. Electoral Studies, 32, 644-657.