Pakistan’s 2018 general election campaign is over. And now, on this tampered playing field — assuming that voters are allowed to cast their ballots without interference on Wednesday — everything rests in the hands of the 106 million Pakistanis who have registered to vote.

As civic duties go, nothing tops the act of casting one’s vote. And in terms of self-interest, this is the one chance for ordinary citizens to elect not only their representative, but, in doing so, to help decide the policies that will affect them.

By casting a vote on the ballot, an ordinary citizen sets up the incentives that govern the behaviour of politicians: does one reelect the politician who brought in funding for a girls’ school, or the one who got a new road built?

Does one vote for the same politician every term even if they switch parties? Does one vote for the same party regardless of the politician running in the constituency? Does one vote for patronage, or for actions in parliament?

To take all these considerations into account is a lot to ask from a single vote. Voting, by its very nature, is a blunt tool. But it’s the only one every single citizen has — and this, of course, is precisely what defines a democracy.

A field of study in political science focuses on theory and uses empirical tools to understand how it is that voters actually vote in various contexts.

The theoretical literature gives us a range of assumptions and factors that could affect voting behaviour. It’s keeping that literature in mind that I’ve attempted to list some of the main factors that Pakistani voters need to juggle in their decision tomorrow.

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First, in a parliamentary system, you, as a voter, do not vote for the prime minister directly.

You vote for the candidate in your constituency, who may belong to a party or be independent.

But you are aware, because you are a voter with some sophistication, that by voting for this candidate, you are affecting the probability that you get the government and the prime minister you want.

You may also take into account the votes of those around you, because that too affects the probability of your candidate and party winning. So, by definition, your vote is a mixture of candidate and party preference.

In general, if the ideologies of the political parties running are more or less convergent, candidate preference may trump party preference for voters.

But in a deeply polarised election — such as the current one — party preferences may become paramount.

The decision also depends on the individual voter’s preferences on national versus constituency politics — does one care more strongly about national politics and policy, which is influenced by the party in power, or about local politics?

If one’s constituency representative affects national policy, even a local preference may translate into national policy.

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Second, beyond campaign promises and party manifestoes is a great deal of information about the actual behaviour of parties while in office, which tells you far more about how they will perform than their promises do.

At its core, voting is a principal-agent problem — you are the principal and the politician is your agent — and you can deduce the politician’s type (whether good or bad) and their effort (whether they work hard or shirk), albeit imperfectly, from their past behaviour.

You have this retrospective information only for candidates and parties who have been in power. Use it.

Third, voting is a blunt instrument on policy, because politicians and parties have policy platforms that are multidimensional. You are going to agree with some of their policies, and not with others.

Ultimately, the voting decision is based on your personal ranking of what policy issues matter most to you and the payoff you derive from each party’s policy on that issue.

You can’t choose each dimension of policy — for instance, the economy, delivery of social services, corruption, conservatism or liberalism, civilian supremacy and so on — according to your preferences, so choose what matters to you most, and choose the party and candidate whose policy platform maximises your utility.

Remember the bargain you strike — it will be with you for the next five years, should your candidate win.

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Fourth, remember that voting, and democracy, is a process. If you consider yourself to have a set of bad choices, make the choice that is least bad.

If you would like better choices, vote in a manner that will encourage the introduction of a better choice in the next election: if you want more liberal choices on the ballot, vote for the most liberal choice in the set you have now; if you want all politicians to engage in less patronage and more legislating, vote for the candidate who focuses the most on the latter and the least on the former, and so on.

Voting is messy and imperfect. In Pakistan, there are further complications. One is horse-trading, which means the candidate-party match is (wildly) unstable.

Voters also find it difficult to discern the exact responsibility of their federal legislators — who tend to be rewarded not for their votes in parliament but for the patronage they provide their constituents, reflecting that voter confusion — versus their provincial legislators or local elected officials.

This is because the division of responsibilities for elected officials at various levels is not well understood, nor is how these responsibilities differ relative to the duty of bureaucrats.

Adding to the confusion is the fact that the 18th Amendment devolved a good deal of federal policymaking to the provincial level, and that provincial elections occur at the same time as the general election.

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Ultimately, voting is visceral. In the United States, there is a sense that voters vote for the presidential candidate they most identify with (which, needless to say, may not make for the best of decisions).

But consider it the most sacred of civic duties — and the burden of information gathering, parsing and decision-making on all these dimensions rests on the shoulders of the voter.

Here’s wishing everyone luck and wisdom in making that decision.

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