The New York Times notes that RSVP rates seem to be declining, here is another account with a similar conclusion. One Evite.com executive notes that last year’s invitation response rate ran about 63 percent. A variety of wedding and event planners note that people are ignoring invitations to an increasing degree. At the last minute they decide whether or not to show up, but in the meantime you do not hear a peep from them

Perhaps people are experiencing a kind of invitation fatigue. Imagine receiving ten or fifteen invitations a week. The value of time is higher than ever before, and many people wait to see what else will come along. Ironically the Evite.com service may be part of the problem. You can see who else has been invited, and who else has already accepted. You also know that it is especially easy for other people to invite you to other events. In other words, you gain by waiting and sampling more information.

We may be missing out on gains from trade, since the incentive to organize an event declines accordingly. Even if an event is organized, it is more costly to plan it.

Of course organizers make follow-up calls but this only worsens the collective problem in the longer run. Everyone waits to RSVP, figuring they will receive a call in any case.

The economist will wonder what alternative institutions could address this problem. Evite.com could assign a “reliable response” index to each person, akin to an ebay credit rating. Or organizers could send an incomplete invitation. You receive the invitation, but not the exact address or some other critical piece of information. Only those for RSVP are sent the critical information. This proposal, however, has two problems. First, you exclude those who are simply careless rather than manipulating the process. Second, a new convention may evolve whereby you say yes no matter what, whether or not you come. It appears that this practice is already common in Washington, D.C.

Similarly, it does not work to subsidize those who respond early. (For instance lower the overall quality of your event, but promise a bonus to early respondents, such as a hotel discount or a lottery ticket for a door prize. ) You can make early response a dominant strategy, but unless you can punish non-attenders this will not solve the problem. You need to reward both an early and truthful response. Asking invitees to post a bond solves the economic problem, but probably does not help your friendships, especially if the bond is confiscated. If readers have any solutions to the RSVP problem please send them in!