{"id":304,"date":"2014-09-28T19:49:30","date_gmt":"2014-09-29T03:49:30","guid":{"rendered":"http:\/\/steveharoz.com\/blog\/?p=304"},"modified":"2014-09-28T19:49:30","modified_gmt":"2014-09-29T03:49:30","slug":"mysterious-origins-of-hypotheses-in-visualization-and-chi","status":"publish","type":"post","link":"http:\/\/steveharoz.com\/blog\/2014\/mysterious-origins-of-hypotheses-in-visualization-and-chi\/","title":{"rendered":"Mysterious Origins of Hypotheses in Visualization and CHI"},"content":{"rendered":"<p>For years, I&#8217;ve noticed a strange practice in Visualization and CHI. When describing a study, many papers list a series of predictions\u00a0and number them as\u00a0H1, H2, H3&#8230; For example:<\/p>\n<ul>\n<li><strong>H1<\/strong>:\u00a0Red graphs\u00a0are\u00a0better than blue graphs<\/li>\n<li><strong>H2<\/strong>: Participants will read vertical bar graphs more quickly than horizontal bar\u00a0graphs<\/li>\n<\/ul>\n<p>I have never seen this practice\u00a0in any other\u00a0field, and I was curious as to the origin.<\/p>\n<h2>Half Hypotheses<\/h2>\n<p>Although\u00a0these statements are referred to as &#8216;hypotheses&#8217;, they&#8217;re not&#8230; at least, not completely. They are predictions. The distinction is subtle but important.\u00a0Here&#8217;s the scientific definition of <em>hypothesis<\/em>\u00a0according to The National Academy of Sciences:<\/p>\n<blockquote><p>A tentative explanation for an observation, phenomenon, or scientific problem that can be tested by further investigation&#8230;<\/p><\/blockquote>\n<p>The key\u00a0word here is\u00a0<strong>explanation<\/strong>.\u00a0A hypothesis is not simply a guess about the result of an experiment. It is a proposed explanation that can\u00a0predict the outcome of\u00a0an experiment. A hypothesis has two components: (1) an explanation and (2) a prediction. A prediction simply isn&#8217;t\u00a0useful on its own. If I flip a coin and correctly guess &#8220;heads&#8221;, it doesn&#8217;t tell me anything\u00a0other than that I made a lucky guess. A hypothesis would be:\u00a0<em>the coin is\u00a0unevenly weighted, so it is far more likely to land heads-up<\/em>. It has an explanation (uneven weighting) that allows for a prediction (frequently landing\u00a0heads-up).<\/p>\n<h2>The Origin of H1, H2, H3&#8230;<\/h2>\n<p>Besides the unusual use of the term &#8220;hypothesis&#8221;, where does the numbering style come from? It appears in\u00a0many\u00a0IEEE InfoVis and ACM CHI papers going back to at least\u00a0<a title=\"1996\" href=\"http:\/\/www.sigchi.org\/chi96\/proceedings\/papers\/Schumann\/chi96fi.html\" target=\"_blank\">1996<\/a> (maybe earlier?). However,\u00a0I&#8217;ve never seen it in psychology or social science journals. The best candidate I can think of for the origin of\u00a0this numbering is a misunderstanding of\u00a0null hypothesis testing, which can be best explained with an example. Here is a null hypothesis with\u00a0two alternative hypotheses:<\/p>\n<ul>\n<li><strong>H<sub>0<\/sub><\/strong>: Objects do not affect each other&#8217;s motion (null hypothesis)<\/li>\n<li><strong>H<sub>1<\/sub><\/strong>: Objects attract\u00a0each other, so a ball should fall towards the Earth<\/li>\n<li><strong>H<sub>2<\/sub><\/strong>: Objects repel each other, so a ball should fly away from the Earth<\/li>\n<\/ul>\n<p>Notice that the\u00a0hypotheses are mutually exclusive, meaning only one can be true. In contrast, Vis\/CHI-style hypotheses\u00a0are each independent, and all or none of them can be true. I&#8217;m not sure how one came to be transformed into the other, but it&#8217;s my best guess for the origins.<\/p>\n<h2>Unclear<\/h2>\n<p>On top of my concerns about diction or utility, referring to statements by number hurts clarity. Repeatedly scrolling back and forth trying\u00a0to remember &#8220;which one was H3 again?&#8221; makes reading frustrating and unnecessarily\u00a0effortful. It&#8217;s a bad practice to label variables in code as var1 and var2. Why should it be better to refer to written concepts numerically? Let&#8217;s put an end to these numbered half-hypotheses in Vis and CHI.<\/p>\n<p><em>Do you agree with this perspective and proposed origin? Can you find an example\u00a0of this H numbering from before 1996? Or in another field?<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>For years, I&#8217;ve noticed a strange practice in Visualization and CHI. When describing a study, many papers list a series of predictions\u00a0and number them as\u00a0H1, H2, H3&#8230; For example: H1:\u00a0Red graphs\u00a0are\u00a0better than blue graphs H2: Participants will read vertical bar graphs more quickly than horizontal bar\u00a0graphs I have never seen this practice\u00a0in any other\u00a0field, and [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"activitypub_content_warning":"","activitypub_content_visibility":"","activitypub_max_image_attachments":3,"activitypub_interaction_policy_quote":"anyone","activitypub_status":"","footnotes":""},"categories":[2,4,6],"tags":[15,21],"class_list":["post-304","post","type-post","status-publish","format-standard","hentry","category-chi","category-science","category-visualization","tag-infovis","tag-science"],"_links":{"self":[{"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/posts\/304","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/comments?post=304"}],"version-history":[{"count":1,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/posts\/304\/revisions"}],"predecessor-version":[{"id":1359,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/posts\/304\/revisions\/1359"}],"wp:attachment":[{"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/media?parent=304"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/categories?post=304"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/steveharoz.com\/blog\/wp-json\/wp\/v2\/tags?post=304"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}