{"id":809,"date":"2025-12-23T10:35:11","date_gmt":"2025-12-23T10:35:11","guid":{"rendered":"https:\/\/alandix.com\/statistics\/?page_id=809"},"modified":"2025-12-23T10:41:55","modified_gmt":"2025-12-23T10:41:55","slug":"chapter-8","status":"publish","type":"page","link":"https:\/\/alandix.com\/statistics\/second-edition\/toc\/chapter-8\/","title":{"rendered":"Chapter 8: Common issues"},"content":{"rendered":"<div class=\"embedurl\" data-url=\"https:\/\/alandix.com\/books\/hcistats\/content2e\/chaps\/chap-8.html\" ><!--  Chapter 8 Common issues  -->\n\n<script>\nvar chapnos = 8;\nvar json_url = \"https:\\\/\\\/alandix.com\\\/books\\\/hcistats\\\/content2e\\\/chaps\\\/chap-8.json\";\n<\/script>\n\n\n\n\n\n\n<h3> Contents <\/h3>\n<div class=\"toc\">\n<dl>\n<dt>8.1&nbsp;&nbsp;Cherry picking<\/dt><dd><dl>\n<dt>8.1.1&nbsp;&nbsp;Multiple tests<\/dt>\n<dt>8.1.2&nbsp;&nbsp;Multiple statistics<\/dt>\n<dt>8.1.3&nbsp;&nbsp;Outliers<\/dt>\n<dt>8.1.4&nbsp;&nbsp;Post-hoc hypothesis<\/dt>\n<dt>8.1.5&nbsp;&nbsp;The file drawer effect<\/dt>\n<\/dl><\/dd>\n<dt>8.2&nbsp;&nbsp;Inter-related factors<\/dt><dd><dl>\n<dt>8.2.1&nbsp;&nbsp;Non-independently controllable factors<\/dt>\n<dt>8.2.2&nbsp;&nbsp;Correlated features<\/dt>\n<\/dl><\/dd>\n<dt>8.3&nbsp;&nbsp;Everything is random<\/dt>\n<dt>8.4&nbsp;&nbsp;The same or worse<\/dt><dd><dl>\n<dt>8.4.1&nbsp;&nbsp;Everything is unlikely<\/dt>\n<dt>8.4.2&nbsp;&nbsp;Numeric data<\/dt>\n<dt>8.4.3&nbsp;&nbsp;More complex &lsquo;or worse&rsquo;<\/dt>\n<dt>8.4.4&nbsp;&nbsp;Post-hoc corrections<\/dt>\n<\/dl><\/dd>\n<dt>8.5&nbsp;&nbsp;What you can say &ndash; phenomena and statisticians<\/dt>\n<\/dl><\/div>\n\n\n<h3> Glossary items referenced in this chapter <\/h3>\n<div class=\"toc\">\n<a href=\"https:\/\/alandix.com\/glossary\/hcistats\/bayesian%20reasoning\">Bayesian reasoning<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/bayesian%20statistics\">Bayesian statistics<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/bayesian%20test\">Bayesian test<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/bias\">bias<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/bonferroni%20correction\">Bonferroni correction<\/a><\/strong>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/cherry%20picking\">cherry picking<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/coin%20tossing\">coin tossing<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/confidence%20interval\">confidence interval<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/confirmation%20bias\">confirmation bias<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/continuous%20distribution\">continuous distribution<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/emergent%20patterns\">emergent patterns<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/estimated%20standard%20deviation\">estimated standard deviation<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/extreme%20values\">extreme values<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/factorial\">factorial<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/fair%20coin\">fair coin<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/false%20negative\">false negative<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/file%20drawer%20effect\">file drawer effect<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/fishing%20expedition\">fishing expedition<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/hypothesis%20testing\">hypothesis testing<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/inter-related%20factors\">inter-related factors<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/likelihood\">likelihood<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/machine%20learning\">machine learning<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/mean\">mean (&amp;mu;)<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/multiple%20statistics\">multiple statistics<\/a><\/strong>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/multiple%20tests\">multiple tests<\/a><\/strong>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/multiplicity%20control\">multiplicity control<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/negative%20results\">negative results<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/network%20data\">network data<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/non-independence\">non-independence<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/non-significant%20result\">non-significant result<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/nonparametric%20statistics\">nonparametric statistics<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/normal%20distribution\">Normal distribution<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/null%20hypothesis\">null hypothesis<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/numeric%20data\">numeric data<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/odds%20ratio\">odds ratio<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/one-tailed%20test\">one-tailed test<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/outliers\">outliers<\/a><\/strong>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/p-curve\">p-curve<\/a><\/strong>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/p-hacking\">p-hacking<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/p-value\">p-value<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/positive%20results\">positive results<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/post-hoc%20hypothesis\">post-hoc hypothesis<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/posterior%20distribution\">posterior distribution<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/pre-registration\">pre-registration<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/prior%20distribution\">prior distribution<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/probability%20distribution\">probability distribution<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/r\">R<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/response%20time\">response time<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/sample\">sample<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/sample%20variance\">sample variance<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/selective%20publishing\">selective publishing<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/significance%20level\">significance level<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/significance%20test\">significance test<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/significant%20range\">significant range<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/significant%20result\">significant result<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/spss\">SPSS<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/standard%20deviation\">standard deviation (s.d., &amp;sigma;)<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/starting%20hypothesis\">starting hypothesis<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/statistical%20power\">statistical power<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/statistical%20significance\">statistical significance<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/student%27s%20t%20distribution\">Student&#039;s t distribution<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/student%27s%20t-test\">Student&#039;s t-test<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/systematic%20effects\">systematic effects<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/task%20completion%20time\">task completion time<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/traditional%20statistics\">traditional statistics<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/two-tailed%20test\">two-tailed test<\/a>, <strong><a href=\"https:\/\/alandix.com\/glossary\/hcistats\/type%20ii%20error\">Type II error<\/a><\/strong>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/uniform%20prior\">uniform prior<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/user%20experience\">user experience<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/user%20interface\">user interface<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/user%20interface%20properties\">user interface properties<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/user%20studies\">user studies<\/a>, <a href=\"https:\/\/alandix.com\/glossary\/hcistats\/variance\">variance<\/a><\/div>\n\n\n<!-- ?php\n\tif ( @$page['prolog_examples'] ):\n?>\n<h3> Prolog examples (from 1st ed.) <\/h3>\n<!-- ?php\n\techo $page['prolog_examples'];\n?>\n<!-- ?php\n\tendif; \/\/ @$page['prolog_examples']\n? -->\n\n<\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":2,"featured_media":0,"parent":801,"menu_order":8,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_themeisle_gutenberg_block_has_review":false,"footnotes":""},"class_list":["post-809","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/pages\/809","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/comments?post=809"}],"version-history":[{"count":2,"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/pages\/809\/revisions"}],"predecessor-version":[{"id":841,"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/pages\/809\/revisions\/841"}],"up":[{"embeddable":true,"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/pages\/801"}],"wp:attachment":[{"href":"https:\/\/alandix.com\/statistics\/wp-json\/wp\/v2\/media?parent=809"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}