http://homepage.cs.uiowa.edu/~dwjones/voting/cogel/
Jones on Human Factors, Slide 7

 

Strange Instructions on many Florida Ballots

DO NOT VOTE FOR MORE
THAN THE NUMBER
INDICATED FOR EACH OFFICE
For President
(Vote for Group)

Charlotte, Lake and Liberty Counties added one word:
     (Vote for One Group)     

 

Overvote rates for "vote for group" (2-column ballots)


Adding the word ONE (2-column ballots)


Over 99,000 voters saw "vote for group" on 2-column ballots;
    of them, about 7.4% cast overvotes.
Over 72,000 voters saw "vote for one group" on 2-column ballots;
    of them, about 4.3% cast overvotes.

In sum, this one word omission may have caused the loss of about 3000 presidential votes!