{"id":112,"date":"2015-05-30T21:27:09","date_gmt":"2015-05-30T21:27:09","guid":{"rendered":"http:\/\/blog.ufes.br\/fabiomolinares\/?p=112"},"modified":"2015-05-30T22:04:47","modified_gmt":"2015-05-30T22:04:47","slug":"adding-regression-line-equation-and-r-square-on-graph","status":"publish","type":"post","link":"https:\/\/blog.ufes.br\/fabiomolinares\/2015\/05\/30\/adding-regression-line-equation-and-r-square-on-graph\/","title":{"rendered":"Adding regression line equation and R Square on graph"},"content":{"rendered":"
set.seed<\/span>(34567<\/span>)<\/span>\r\n<\/code><\/pre>\n
x <-<\/span> runif(10)<\/span>; <\/span>y <-<\/span> 4*x<\/span>+<\/span>rnorm<\/span>(<\/span>10<\/span>) <\/span>\r\nfit <-<\/span> lm<\/span>(<\/span>y<\/span>~<\/span>x<\/span>)<\/span>\r\nr2 <-<\/span> summary<\/span>(<\/span>fit<\/span>)$<\/span>r.squared\r\n\r\n<\/span># plot data and regression line<\/span>\r\nplot<\/span>(<\/span>x<\/span>,<\/span> y<\/span>)<\/span>\r\nabline<\/span>(<\/span>fit<\/span>,<\/span> col<\/span>=<\/span>2<\/span>)<\/span>\r\n\r\n# add text to plot with legend()\r\n<\/span><\/code>legend<\/span>(<\/span>'topleft'<\/span>,<\/span> title<\/span>=<\/span>'option 1'<\/span>,<\/span> \r\nlegend<\/span>=<\/span>sprintf<\/span>(<\/span>\"y = %3.2fx %+3.2f, R\\UB2 = %3.2f\"<\/span>, \r\n<\/span><\/code>coef<\/span>(<\/span>fit<\/span>)[<\/span>2<\/span>]<\/span><\/code>,<\/span><\/code>coef<\/span>(<\/span>fit<\/span>)[<\/span>1<\/span>]<\/span><\/code>,<\/span> r2<\/span>),<\/span> bty<\/span>=<\/span>'n'<\/span>,<\/span> cex<\/span>=<\/span>0.7<\/span>)<\/span> \r\n\r\n# if you prefer a space between plus\/minus and b<\/span>\r\nb<-<\/code>coef<\/span>(<\/span>fit<\/span>)[<\/span>1<\/span>]\r\n<\/span><\/code>if<\/span>(<\/span>b<\/span><<\/span>0<\/span>)<\/span> {b<\/span>_sign<\/span>=<\/span>'-'<\/span>;<\/span> b<\/span>=<\/span>-<\/span>b<\/span>}<\/span> else<\/span> {b<\/span>_sign<\/span>=<\/span> '+'<\/span>}\r\n \r\n<\/span>legend<\/span>(<\/span>'topright'<\/span>,<\/span> title<\/span>=<\/span>'option 2'<\/span>,<\/span> \r\nlegend<\/span>=<\/span>sprintf<\/span>(<\/span>\"y = %3.2f x %s %3.2f, R\\UB2 = %3.2f\"<\/span>, \r\n<\/span>coef<\/span>(<\/span>fit<\/span>)[<\/span>2<\/span>]<\/span><\/span>,b<\/span>_sign<\/span>,<\/span>b<\/span><\/span>,<\/span>r2<\/span>),<\/span> bty<\/span>=<\/span>'n'<\/span>,<\/span>cex<\/span>=<\/span>0.7<\/span>)<\/span><\/code><\/pre>\n
\n
Important<\/span>: R\\UB2B2<\/strong> defined R square symbol. B2<\/strong> is the hex code for UTF-8 character\u00a0\u00b2<\/strong> and \\U<\/strong> is a control sequence that will call that character.<\/span><\/code><\/p>\n<\/blockquote>\n
\u00a0\r\n\"regression1\"<\/a>\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"
set.seed(34567) x <- runif(10); y <- 4*x+rnorm(10) fit <- lm(y~x) r2 <- summary(fit)$r.squared # plot data and regression line plot(x, y) abline(fit, col=2) # add text to plot with legend() legend(‘topleft’, title=’option 1′, legend=sprintf(“y = %3.2fx %+3.2f, R\\UB2 = %3.2f”, coef(fit)[2],coef(fit)[1], r2), bty=’n’, cex=0.7) # if you prefer a space between plus\/minus and b b<-coef(fit)[1] […]<\/p>\n","protected":false},"author":38,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"_uag_custom_page_level_css":"","footnotes":""},"categories":[5],"tags":[],"class_list":["post-112","post","type-post","status-publish","format-standard","hentry","category-r"],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"Fabio Fajardo","author_link":"https:\/\/blog.ufes.br\/fabiomolinares\/author\/fabio-molinares\/"},"uagb_comment_info":184,"uagb_excerpt":"set.seed(34567) x <- runif(10); y <- 4*x+rnorm(10) fit <- lm(y~x) r2 <- summary(fit)$r.squared # plot data and regression line plot(x, y) abline(fit, col=2) # add text to plot with legend() legend('topleft', title='option 1', legend=sprintf(\"y = %3.2fx %+3.2f, R\\UB2 = %3.2f\", coef(fit)[2],coef(fit)[1], r2), bty='n', cex=0.7) # if you prefer a space between plus\/minus and b b<-coef(fit)[1]…","_links":{"self":[{"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/posts\/112","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/users\/38"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/comments?post=112"}],"version-history":[{"count":24,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/posts\/112\/revisions"}],"predecessor-version":[{"id":138,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/posts\/112\/revisions\/138"}],"wp:attachment":[{"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/media?parent=112"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/categories?post=112"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.ufes.br\/fabiomolinares\/wp-json\/wp\/v2\/tags?post=112"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}