[EM] Truncation error in STV

[Olli Salmi]

At 17:25 -0400 4.8.2003, Dgamble997 at aol.com wrote:
>The point he was trying to make is that ERS97 gives the impression 
>that vote totals are accurate to 0.01 votes and that in fact they 
>are not.
>
>Take the following example:
>
>A surplus of 20 votes is to be transferred. This surplus arises from 
>a candidate achieving a quota after having 45 votes transferred to 
>him/her. Each vote is transferred at a value of 0.44 to 2 decimal 
>places to the next candidate. 19.8 votes are transferred not 20, 0.2 
>votes are lost due to rounding to 2 dp. In order to obtain accurate 
>totals to 2 dp individual votes must be taken to 3,4 or more dp.( 
>0.4444 X 45 =  19.998).

Thanks for the reply. How do you get "about (number of digits in 
total votes)+1" from this? What are the complexities? Why can't we 
round off 19.998 to 20.00? Is it because the rounding error might 
help a candidate to reach the quota?

Olli Salmi