At a 90-10 division of opinion, rather than 50-50, still at 95 percent confidence, sampling error for 1,000 interviews is +/- 2 points, not 3. For a sample of 100 cases – roughly the minimum sample size ABC News will report – the error margin is +/- 10 points at a 50-50 percent division, +/- 8.5 points at 75-25 percent and +/- 6 points at 90-10 percent. (ABC News polls at times will oversample small populations to increase their sample size to a level we consider reliably reportable.) Show how they are getting these “margin of sampling errors” above, using specific values in the relevant formula to show you get the margin of error percentages listed.