{"id":1363,"date":"2023-06-22T02:20:29","date_gmt":"2023-06-22T02:20:29","guid":{"rendered":"https:\/\/content.one.lumenlearning.com\/introstatstest\/chapter\/conditions-for-anova-learn-it-3\/"},"modified":"2025-05-16T22:53:34","modified_gmt":"2025-05-16T22:53:34","slug":"conditions-for-anova-learn-it-3","status":"publish","type":"chapter","link":"https:\/\/content.one.lumenlearning.com\/introstatstest\/chapter\/conditions-for-anova-learn-it-3\/","title":{"raw":"Conditions for ANOVA - Learn It 3","rendered":"Conditions for ANOVA &#8211; Learn It 3"},"content":{"raw":"<section class=\"textbox learningGoals\">\r\n<ul>\r\n\t<li><span data-sheets-value=\"{&quot;1&quot;:2,&quot;2&quot;:&quot;Check the conditions for a one-way ANOVA hypothesis test&quot;}\" data-sheets-userformat=\"{&quot;2&quot;:12801,&quot;3&quot;:{&quot;1&quot;:0},&quot;12&quot;:0,&quot;15&quot;:&quot;arial&quot;,&quot;16&quot;:10}\">Check the conditions for a one-way ANOVA hypothesis test<\/span><\/li>\r\n<\/ul>\r\n<\/section>\r\n<h2>Variability<\/h2>\r\n<p>The third condition is about the variability within groups.<\/p>\r\n<p>The groups being compared should have <strong>equal or similar variability<\/strong> within their groups. There are formal tests that can be used to assess the similarity of variability among ANOVA groups, but they are beyond the scope of this course.<\/p>\r\n<p>Instead, we can visually estimate variability by comparing boxplots of data or numerically comparing the standard deviations provided in summary statistics. Remember that the box in a boxplot visually represents the middle [latex]50\\%[\/latex] of the data and is the size of the interquartile range. While this is not a measurement of the standard deviation, a boxplot allows us to visually compare the spread or variability in each group.<\/p>\r\n<section class=\"textbox keyTakeaway\">\r\n<h3>variability in ANOVA<\/h3>\r\n<p>A good rule of thumb is:<\/p>\r\n<ul>\r\n\t<li>If the sample sizes are equal, the largest standard deviation can be no more than two times the smallest standard deviation.<\/li>\r\n\t<li>If the sample sizes are different, the standard deviations need to be really similar.<\/li>\r\n<\/ul>\r\n<\/section>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]2179[\/ohm2_question]<\/section>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]2180[\/ohm2_question]<\/section>","rendered":"<section class=\"textbox learningGoals\">\n<ul>\n<li><span data-sheets-value=\"{&quot;1&quot;:2,&quot;2&quot;:&quot;Check the conditions for a one-way ANOVA hypothesis test&quot;}\" data-sheets-userformat=\"{&quot;2&quot;:12801,&quot;3&quot;:{&quot;1&quot;:0},&quot;12&quot;:0,&quot;15&quot;:&quot;arial&quot;,&quot;16&quot;:10}\">Check the conditions for a one-way ANOVA hypothesis test<\/span><\/li>\n<\/ul>\n<\/section>\n<h2>Variability<\/h2>\n<p>The third condition is about the variability within groups.<\/p>\n<p>The groups being compared should have <strong>equal or similar variability<\/strong> within their groups. There are formal tests that can be used to assess the similarity of variability among ANOVA groups, but they are beyond the scope of this course.<\/p>\n<p>Instead, we can visually estimate variability by comparing boxplots of data or numerically comparing the standard deviations provided in summary statistics. Remember that the box in a boxplot visually represents the middle [latex]50\\%[\/latex] of the data and is the size of the interquartile range. While this is not a measurement of the standard deviation, a boxplot allows us to visually compare the spread or variability in each group.<\/p>\n<section class=\"textbox keyTakeaway\">\n<h3>variability in ANOVA<\/h3>\n<p>A good rule of thumb is:<\/p>\n<ul>\n<li>If the sample sizes are equal, the largest standard deviation can be no more than two times the smallest standard deviation.<\/li>\n<li>If the sample sizes are different, the standard deviations need to be really similar.<\/li>\n<\/ul>\n<\/section>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm2179\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=2179&theme=lumen&iframe_resize_id=ohm2179&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm2180\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=2180&theme=lumen&iframe_resize_id=ohm2180&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n","protected":false},"author":8,"menu_order":17,"template":"","meta":{"_candela_citation":"[]","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"part":1348,"module-header":"learn_it","content_attributions":[],"internal_book_links":[],"video_content":null,"cc_video_embed_content":{"cc_scripts":"","media_targets":[]},"try_it_collection":null,"_links":{"self":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/1363"}],"collection":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/users\/8"}],"version-history":[{"count":5,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/1363\/revisions"}],"predecessor-version":[{"id":6841,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/1363\/revisions\/6841"}],"part":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/parts\/1348"}],"metadata":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/1363\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/media?parent=1363"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapter-type?post=1363"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/contributor?post=1363"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/license?post=1363"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}