Docs: coercion resistance vs receipt-freeness

[dsernst]

One other nit: https://docs.siv.org/compare conflates coercion resistance and vote selling. These are actually two different things, and have different definitions in the literature (see the Bernhard SOK linked in my original comment).

Coercion resistance = I cannot collaborate with an attacker to prove the way I voted. E.g., an attacker sits with me while I'm voting to verify that I selected their options. Receipt freeness (Vote selling resistance) = I cannot prove the way I voted after the fact.

A system might actually be receipt free, and not coercion resistant. Consider a system that, when a user submits a vote, does not allow the user to re-vote or spoil the ballot, but also provides no receipt or method of verification. That system will be receipt free -- the voter has no way to prove after the fact that they cast a ballot in any particular way -- but not coercion resistant because an attacker watching them vote can confirm how they're voting.

Originally posted by @mspecter in #181 (comment)

[arianabuilds]

Entry Summary for HACK SIV @ DEF CON 2024

Thanks again for participating! This submission earned $45.35 from SIV and $60.00 from the public vote, for a total of $105.35.

Here's what we noted in our evaluation:

What's interesting about this submission

• Links to reference material in published paper, going into more depth

What takes away from it

• The table is meant to be a high-level summary (eg it doesn't break out Accessibility into Mobility, Vision, Motor, etc)
• Unclear how much the added complexity really helps, or if it would make it harder to read the table

Issue to track getting paid: siv-org/hack.siv.org#11