{"id":226,"date":"2004-06-06T19:42:17","date_gmt":"2004-06-06T23:42:17","guid":{"rendered":"http:\/\/shermandorn.com\/wordpress\/?p=226"},"modified":"2004-06-06T19:42:17","modified_gmt":"2004-06-06T23:42:17","slug":"functional-data-analysis","status":"publish","type":"post","link":"https:\/\/shermandorn.com\/?p=226","title":{"rendered":"Functional data analysis"},"content":{"rendered":"<p>Every once in a while, I choose some form of &#8220;brain candy&#8221; to read for work&#151;something that&#8217;s out of my field and that&#8217;s just fun in some sense, because there&#8217;s no pressure other than the challenge of reading something new.  Because of something an editor suggested to me, I decided to see what <a href=\"http:\/\/ego.psych.mcgill.ca\/misc\/fda\/\">functional data analysis<\/a> is.  Why is an historian reading this?  It has to do with the net-flow research in that I&#8217;m really looking at a step function (net flow as a function of the grade) but one that one could smooth in various ways and then look at the smoothed curves as the object of analysis.<\/p>\n<p><!--more--><br \/>\nWhen I was at Vanderbilt for a postdoc and looking at <a href=\"http:\/\/www.interventioncentral.org\/htmdocs\/interventions\/cbmwarehouse.shtml\">curriculum-based measurement<\/a> data for K-12 students, my brain candy at that time was looking at locally weighted regression as a smoothing device (1).  Functional data analysis takes smoothing one step further by providing tools to make the smoothed curves differentiable.<\/p>\n<p>Arbitrary?  Certainly, but the advocates of functional data analysis point out that all analyses assume some specificity that really isn&#8217;t there, including just the raw data.  That willingness to transform data before analysis is the hallmark of John Tukey&#8217;s exploratory approach.  So, the argument goes, why not make some reasonable assumptions about an underlying function and see what you can make of that?<\/p>\n<p align=\"center\"><strong>Reference<\/strong><\/p>\n<p>Cleveland, W. S. (1979) Robust locally weighted regression and smoothing scatterplots. <cite>Journal of the American Statistical Association<\/cite>, 74, 829-836.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Every once in a while, I choose some form of &#8220;brain candy&#8221; to read for work&#151;something that&#8217;s out of my field and that&#8217;s just fun in some sense, because there&#8217;s no pressure other than the challenge of reading something new. Because of something an editor suggested to me, I decided to see what functional data [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_hide_featured_image":false,"_jetpack_featured_image_duplicate_dismissed":0,"_jetpack_feature_clip_id":0,"_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},"jetpack_post_was_ever_published":false},"categories":[3],"tags":[],"class_list":["post-226","post","type-post","status-publish","format-standard","hentry","category-random-comments"],"jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/pag0MB-3E","jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/shermandorn.com\/index.php?rest_route=\/wp\/v2\/posts\/226","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shermandorn.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/shermandorn.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/shermandorn.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/shermandorn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=226"}],"version-history":[{"count":0,"href":"https:\/\/shermandorn.com\/index.php?rest_route=\/wp\/v2\/posts\/226\/revisions"}],"wp:attachment":[{"href":"https:\/\/shermandorn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=226"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/shermandorn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=226"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/shermandorn.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=226"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}