{"id":15570,"date":"2014-08-09T07:07:05","date_gmt":"2014-08-09T07:07:05","guid":{"rendered":""},"modified":"2014-08-09T07:07:05","modified_gmt":"2014-08-09T07:07:05","slug":"report-6-on-the-six-californias-signature-verification-process","status":"publish","type":"post","link":"https:\/\/calitics.com\/index.php\/2014\/08\/09\/report-6-on-the-six-californias-signature-verification-process\/","title":{"rendered":"Report #6 on the Six Californias Signature Verification Process"},"content":{"rendered":"

Alameda County finally reported their raw signature count! According to Friday’s update<\/a> from the SoS, they had 51,366 raw signatures (a collection rate of 6.4%, the same as the state average), bringing the total raw signature count up to 1,134,746. We’re still waiting for Amador, Inyo, and Trinity to report in, but with only 37,771 registered voters among them, I doubt they’ll contribute more than 2500 signatures to the raw count.<\/p>\n

Also in today’s update are San Francisco’s random sample results. They had a validity rate of 73.7%, bringing the overall validity rate back up to 66.8%. That gives a projection (as of today) of 758,010 valid signatures, not enough to qualify for a full count. (Throwing in my estimate of 2500 raw signatures from the remaining three counties only adds another 1670 signatures, still not enough to get a full count.)<\/p>\n

In my previous report<\/a> I discussed the concept of margin of error<\/a>, so today I calculated it. If a county has a raw count of R, a sample size of S, and a projected validity rate of P (converting the percentage figure to a decimal fraction), then I calculated the margin of error in signatures as R*sqrt(P*(1-P)\/S). (Of course, if S is the same as R, as it is for Alpine, Modoc, and Mono counties, the margin of error is zero.) For example, Kings County had 3,187 raw signatures, a sample size of 500, and a projected validity rate of 0.762. That means the margin of error on the projected 2,428 signatures is 61 signatures (about 2.5%).<\/p>\n

Doing this calculation for all the counties that have reported so far and combining them (taking the square root of the sum of the squares) gives a margin of error of 795 signatures on the sum of the counties’ projections of 79,552, or about 10%.<\/p>\n

Applying that 10% margin of error to my projection of 758,010 means that Mr. Draper could have as few as 682,209 valid signatures or as many as 833,811. (Actually, what it means is that there is a 68% probability that the true figure is between those limits.) But unless the final projected number of valid signatures is above the 767,235 necessary to trigger a full count, we’ll never know how many valid signatures he actually collected.<\/p>\n

One could argue that the criteria for doing a full count should take into consideration the estimated margin of error; that is, instead of projecting more than a fixed number (95% of the amount needed to qualify), if the projected range includes the amount needed to qualify then a full count should be done, but that’s not the way the law is written.<\/p>\n

In a previous report<\/a> I discussed how duplicate signatures were handled. Jim Riley<\/a> has posted a good comment on that. In addition, my colleague David Cary has posted a PDF of his derivation of the estimation formula<\/a> (much clearer and yet more rigorous than my hand-wavy one), as well as the PDF of the SoS’s one page description<\/a> of the formula.<\/p>\n

–Steve Chessin
\n
President, Californians for Electoral Reform (CfER)
\n
www.cfer.org<\/a><\/p>\n

The opinions expressed here are my own and not necessarily those of CfER.<\/p>\n","protected":false},"excerpt":{"rendered":"

Alameda County finally reported their raw signature count! According to Friday’s update<\/a> from the SoS, they had 51,366 raw signatures (a collection rate of 6.4%, the same as the state average), bringing the total raw signature count up to 1,134,746. We’re still waiting for Amador, Inyo, and Trinity to report in, but with only 37,771 registered voters among them, I doubt they’ll contribute more than 2500 signatures to the raw count.<\/p>\n

Also in today’s update are San Francisco’s random sample results. They had a validity rate of 73.7%, bringing the overall validity rate back up to 66.8%. That gives a projection (as of today) of 758,010 valid signatures, not enough to qualify for a full count. (Throwing in my estimate of 2500 raw signatures from the remaining three counties only adds another 1670 signatures, still not enough to get a full count.)<\/p>\n

In my previous report<\/a> I discussed the concept of margin of error<\/a>, so today I calculated it. If a county has a raw count of R, a sample size of S, and a projected validity rate of P (converting the percentage figure to a decimal fraction), then I calculated the margin of error in signatures as R*sqrt(P*(1-P)\/S). (Of course, if S is the same as R, as it is for Alpine, Modoc, and Mono counties, the margin of error is zero.) For example, Kings County had 3,187 raw signatures, a sample size of 500, and a projected validity rate of 0.762. That means the margin of error on the projected 2,428 signatures is 61 signatures (about 2.5%).<\/p>\n","protected":false},"author":6738,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[87],"tags":[11314,11315],"class_list":["post-15570","post","type-post","status-publish","format-standard","hentry","category-87","tag-11314","tag-11315"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack-related-posts":[],"jetpack_shortlink":"https:\/\/wp.me\/p6Pvhz-438","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/posts\/15570","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/users\/6738"}],"replies":[{"embeddable":true,"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/comments?post=15570"}],"version-history":[{"count":0,"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/posts\/15570\/revisions"}],"wp:attachment":[{"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/media?parent=15570"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/categories?post=15570"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/calitics.com\/index.php\/wp-json\/wp\/v2\/tags?post=15570"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}