{"id":3571,"date":"2015-11-25T14:28:08","date_gmt":"2015-11-25T22:28:08","guid":{"rendered":"http:\/\/nnlm.gov\/evaluation\/blog\/?p=3571"},"modified":"2019-09-24T10:13:29","modified_gmt":"2019-09-24T17:13:29","slug":"take-the-pie-leave-the-pie-chart","status":"publish","type":"post","link":"https:\/\/news.nnlm.gov\/nec\/2015\/11\/25\/take-the-pie-leave-the-pie-chart\/","title":{"rendered":"Take The Pie, Leave The Pie Chart"},"content":{"rendered":"

Evaluation and data visualization folks may disagree on the best pie to serve at Thanksgiving dinner.\u00a0 Pumpkin?\u00a0 Pecan?\u00a0 A nice silk pie made with chocolate liqueur and tofu? (Thank you, Alton Brown.)<\/p>\n

\"Pumpkin<\/a><\/p>\n

You see, the whole point of charts is to give people an instantaneous understanding of your findings.\u00a0 Your readers can easily discern differences in bars and lines.\u00a0 In wedges of pie, not so much. Data visualization expert Stephen Few explained the problem during\u00a0this interview<\/a> with the New York Times:<\/em>\u00a0\u201cWhen looking at parts of a whole, the primary task is to rank them to see the relative performance of the parts. That can\u2019t be done easily when relying on angles formed by a slice.\u201d<\/p>\n

(Note:\u00a0 This parts-to-whole angle problem may also explain why most of us can\u2019t understand how our Whole Foods pumpkin pie could possibly have eight servings. Eight? Are you kidding me?)<\/p>\n

So, for today\u2019s pre-Thanksgiving holiday post, I thought I would point you to some online articles about the much used and much vilified pie chart.<\/p>\n

First, here\u2019s an article<\/a>\u00a0by American Evaluation Association\u2019s president-elect John Gargani, arguing for retirement of the venerable pie chart.\u00a0 He make points that are repeated in many anti-pie chart blog posts.\u00a0 But in the interest of objectivity, you should know that agreement to send\u00a0pie charts to the cosmic dust bin is not universal. Here\u2019s a post<\/a> by Bruce Gabrielle of Speaking PowerPoint<\/em> that describes situations where pie charts can shine.<\/p>\n

In general, most experts believe that the times and places to use pie charts are few and far between. If you have found one of those rare times, then here\u2019s a post<\/a> at Better Evaluation with the design tips to follow.<\/p>\n

But for heaven sake, turn off that three-dimensional feature in your pie chart, or in any chart, for that matter. Nobody wants to see that!<\/p>\n

And for humorous examples of what not to do, check out Michael Friendly\u2019s Evil Pies<\/a><\/em> blog,<\/p>\n","protected":false},"excerpt":{"rendered":"

Evaluation and data visualization folks may disagree on the best pie to serve at Thanksgiving dinner.\u00a0 Pumpkin?\u00a0 Pecan?\u00a0 A nice silk pie made with chocolate liqueur and tofu? (Thank you, Alton Brown.) You see, the whole point of charts is to give people an instantaneous understanding of your findings.\u00a0 Your readers can easily discern differences… Read More »<\/a><\/p>\n","protected":false},"author":2959,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"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":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[6],"tags":[],"class_list":["post-3571","post","type-post","status-publish","format-standard","hentry","category-data-visualization"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p8ICUo-VB","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/posts\/3571","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/users\/2959"}],"replies":[{"embeddable":true,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/comments?post=3571"}],"version-history":[{"count":1,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/posts\/3571\/revisions"}],"predecessor-version":[{"id":6473,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/posts\/3571\/revisions\/6473"}],"wp:attachment":[{"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/media?parent=3571"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/categories?post=3571"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/news.nnlm.gov\/nec\/wp-json\/wp\/v2\/tags?post=3571"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}