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weDecide is a web-based application that enables a group of people to make collective decisions in the most efficient manner possible. Community Leaders use the application to create a community with members they choose and then announce votes on questions (for example, should we hire Jones?, should we hold a meeting on Friday at 4?). Community Members then use the application to vote, based on the Quadratic Voting (QV) system. QV ensures that Community Members vote sincerely-that is, in a way that reflects their true intensity of preference about the issue. weDecide aggregates their votes and reports the result to the Community Leader and Community Members.

Because QV ensures that everyone votes sincerely, weDecide produces the best possible decisions that should satisfy everyone. By contrast, ordinary rules for making collective decisions-like majority rule-can produce bad outcomes and can be gamed. In these systems, a majority that does not care very much about an outcome can outvote a minority that cares a lot. By contrast, weDecide ensures that people’s influence on outcomes is commensurate with how much they care about them.

Employers can use weDecide whenever they want groups of employees to make decisions. Applications include:

weDecide can also be used in many other settings. For example:

Quadratic Voting

The core idea behind weDecide is QV, a collective decision-making algorithm invented by cofounder Glen Weyl. The basic intuition behind QV is that when a group of people make a decision together, people who are affected most by the decision should have the most influence over it. Majority rule fails this test because everyone gets one vote regardless of whether the decisions affect them a lot, a little, or not at all. QV allows people to exercise influence in proportion to their interest by giving everyone the ability to cast multiple votes when a decision matters to them, while preventing them from doing so when the decision does not matter to them.

The version of QV used in weDecide works like this. Every Community Member receives from the Community Leader a number of artificial currency units that we call CDCs when (s)he is invited to join the Community. For example, everyone might be given 100 CDCs. Every time the Community Leader poses a question to be voted on, Community Members receive an email that takes them to their account on the website. Community Members can cast as many votes as they want but must pay, in CDCs, the square of the number of votes they cast. For example, 1 vote costs 1 CDC; 2 votes cost 4 CDCs; and 3 votes cost 9 CDCs. The CDCs are subtracted from the Community Member’s account, but after the vote the Community Member’s account is then replenished with CDCs equal to the total spent on the vote divided by the number of group members, if the Community Leader has opted to make refunds available to Community Members. If the Community Leader is only planning on a few votes occurring, she may opt for no refunds.

When a Community Member chooses how many CDCs to spend on votes, he must take into account the fact that if he spends a lot of CDCs today, he will have few to spend on another question he might care about tomorrow. Squaring the cost ensures that he will take proper account of the effect of his vote on the other group members, because this makes the cost of the next vote equal to the number of votes already selected. Weyl has proven mathematically that QV decision-procedures are the only practical methods for optimally aggregating group judgments. They are fast (people simply vote by web or mobile app), cannot be gamed, and produce the correct decisions given people’s information and preferences.

Further information about QV can be found in the following publications (where it is sometimes referred to as Quadratic Vote-Buying).

Collective Decision Engines (CDE)

CDE is a startup founded by Eric Posner and Glen Weyl in 2013 to commercialize QV. Eric is a law professor at the University of Chicago, who has written numerous books and articles on a wide range of subjects. Glen Weyl is an economics professor at the University of Chicago.

Co-Founder E. Glen Weyl
Co-Founder Eric Posner