Technical statistical note: 4 seats in poll means less than 56% odds make
the threshold

Dr. Aaron Lerner Date: 23 January 2015

When you open a newspaper and see that a party has 4 seats in a poll of 500
that means that the odds that they actually would pass the election
threshold of 3.25% of the vote is less than 56%.

In sharp contrast, a party that shows 5 seats in that same poll of 500
enjoys odds of almost 93% of passing the election threshold.

And what if there are a bunch of similar polls carried out at the same time?

If you view the polls in aggregate as one big poll of 2,000 respondents a
party that received 4 seats in each of the polls has odds of less than 62%
that it will pass the election threshold while the party with 5 seats has
99.8% odds of making it in.

Please take note: The above assumes that the polls were perfectly
representative random samples of the voters and that everyone was honest in
their replies AND that there is no correlation between propensity to
actually vote on elections day and party preference.

That’s a lot assumptions.

In any case, the estimate for the 4 seat party was generous because these
calculations assumed that there were no undecided or that the undecided will
either not vote or that if they vote that they will have the same voting
pattern as the decided.

Dr. Aaron Lerner, Director IMRA (Independent Media Review & Analysis)
(Mail POB 982 Kfar Sava)
Tel 972-9-7604719/Fax 972-3-7255730
INTERNET ADDRESS: imra@netvision.net.il
Website: http://www.imra.org.il