{"id":48,"date":"2009-08-05T18:04:16","date_gmt":"2009-08-05T22:04:16","guid":{"rendered":"http:\/\/qimacros.com\/lean-six-sigma-blog\/?p=48"},"modified":"2015-02-13T18:34:00","modified_gmt":"2015-02-13T18:34:00","slug":"normality-is-overrated","status":"publish","type":"post","link":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/normality-is-overrated\/","title":{"rendered":"Normality is Overrated"},"content":{"rendered":"<p>The Six Sigma community seems to be obsessed with whether their data is normal or non-normal. If you&#8217;re using the data for control charts, normality is overrated.<\/p>\n<p>Donald J. Wheeler, author of <em>Advanced Topics in Statistical Process Control<\/em>, \u00a0just published an insightful paper on what he calls,\u00a0Leptokurtophobia&#8211;the abnormal need for normal distributions&#8211;at <a href=\"http:\/\/www.qualitydigest.com\/inside\/quality-insider-column\/do-you-have-leptokurtophobia.html\">http:\/\/www.qualitydigest.com\/inside\/quality-insider-column\/do-you-have-leptokurtophobia.html<\/a>.<\/p>\n<p>Wheeler says: &#8220;We do not need to check the data for normality, nor do we need to define a reference distribution prior to computing limits. Anyone who tells you anything to the contrary is simply trying to complicate your life unnecessarily. &#8221;<\/p>\n<p>&#8220;Transforming the data prior to using them on a process behavior chart is not only bad advice, it is also an outright mistake.&#8221;<\/p>\n<p>All I can say is <em>lose your fear of non-normal data!<\/em> Get on with making the process faster, better and cheaper.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The Six Sigma community seems to be obsessed with whether their data is normal or non-normal. If you&rsquo;re using the data for control charts, normality is overrated. Donald J. Wheeler, author of Advanced Topics in Statistical Process Control, &nbsp;just published an insightful paper on what he calls,&nbsp;Leptokurtophobia&ndash;the abnormal need for normal distributions&ndash;at http:\/\/www.qualitydigest.com\/inside\/quality-insider-column\/do-you-have-leptokurtophobia.html. Wheeler says: [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[31,170],"class_list":["post-48","post","type-post","status-publish","format-standard","hentry","category-six-sigma","tag-data-normality","tag-six-sigma"],"_links":{"self":[{"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/posts\/48","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/comments?post=48"}],"version-history":[{"count":1,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/posts\/48\/revisions"}],"predecessor-version":[{"id":567,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/posts\/48\/revisions\/567"}],"wp:attachment":[{"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/media?parent=48"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/categories?post=48"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.qimacros.com\/lean-six-sigma-blog\/wp-json\/wp\/v2\/tags?post=48"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}