I know that by this point there have been far too many posts related to scientific blunders caused to rounding error. But somehow even though I swore I wouldn’t write about the same thing, coming across this article on google, I just couldn’t resist myself. So yeah, I’m not sure if anyone has mentioned the Patriot missile case in which a 0.0000000000000000000000011001100 binary chopping error caused the death of some 28 soldiers and injured 100 people. Then as course_evaluation has already explained how rounding error caused discrepancies in currency conversion, there was a case where an ATM was giving arbitrary amount of Euro to different pin codes. But as if all this was not enough, rounding error actually caused the change in the parliament make up once in Germany in the elections to the parliament for the state of Schleswig-Holstein!

I shall try and explain this without going into much parliament setup details. Germany has/had this 5% rule which said that if any party won less than 5% of the total votes, the party would lose all those votes and they would be distributed to the other party lists. During election, Green party won the bare minimum of 5% votes but since it had achieved the 5% mark, it could keep its seats. This prevented the Social Democratic Party(SDP) from seating any person from their list. The night after the results were published, someone found out that the greens had actually just won 4.97% of the votes and the program had rounded off the number to integer 5. After, this was found out, seats were recalculated, the greens’ seats were taken and the one extra seat was given to the SDP. Thanks to this error correction, the SDP won a one seat majority in the parliament. It is pretty interesting to note how a rounding error could have changed the country’s future for a few years!
So, lets see, missiles blunders, currency exchange errors, wrong majority in government…Rounding error, What next?