Politicians who really wanted to show they would keep their campaign promises would post bonds, judged by neutral third parties, forfeit if they broke their promises.  Similarly, pundits who really wanted to show they believed their punditry would offer to bet on their claims.  Pundit Tyler Cowen says this would be too much bother:

Bryan Caplan believes that scholars should be ashamed if they do not publicly bet their views.  In contrast I fear this requirement would become a tax upon ideas. How would you feel about an obligation (if only a moral one) for scholars and commentators to publicly reveal the content of their investment portfolios?  Those portfolios are their real bets.  Yet I still favor the privacy norm and I should note that Bryan never has (nor need he) revealed his portfolio to others at GMU, much less to the broader public.

Let's say that I, as a prolific blogger, express opinions on hundreds of economic policy topics, often involving either explicit or implicit predictions.  Then say that hundreds of people wish to bet with me.  Can I not simply turn them all down as a matter of policy and practicality?

If you're wondering, I practice "buy and hold and diversify," with no surprises in the portfolio and a conservative ratio of equity purchases.  But those investment decisions don't necessarily reflect my views on any given day.  I think it is intellectually legitimate (though perhaps not always prudent) to engage in mental accounting and separate those two spheres of my life.  I change my mind lots of times, on many economic issues, but does that mean I have to become an active trader?  I hope not and I'm not going to.

Yes, transaction costs keep investments from closely matching beliefs. For example, my investments have long been mainly in my house, family, job skills, and relationships; I don't have much money for more.  But that wouldn't prevent me, or Tyler, from having hundreds of small token bets on our public claims, at least the claims that lend themselves to bets.  Yes, a bit of a bother, but well worth it if our readers actually cared that we believe what we say, or wanted to track our accuracy.

Yes, most readers and voters probably don't care much about pundit and politician accuracy and sincerity; they mostly want to affiliate with a stately staccato stream of statusful statements.  Slowing this down to post bonds, make bets, or even just think carefully, would just not be worth the tradeoff.  But I'll join most of Tyler's commenters in saying that some of us do care about accuracy and sincerity.  I'm open to bets on my claims, even if that slows me down.