{"id":3902,"date":"2023-07-14T21:02:11","date_gmt":"2023-07-14T21:02:11","guid":{"rendered":"https:\/\/statorials.org\/pt\/cristalizado-r\/"},"modified":"2023-07-14T21:02:11","modified_gmt":"2023-07-14T21:02:11","slug":"cristalizado-r","status":"publish","type":"post","link":"https:\/\/statorials.org\/pt\/cristalizado-r\/","title":{"rendered":"Como usar a fun\u00e7\u00e3o confit() em r"},"content":{"rendered":"<p><\/p>\n<hr>\n<p><span style=\"color: #000000;\">Voc\u00ea pode usar a fun\u00e7\u00e3o <strong>confint()<\/strong> em R para calcular um intervalo de confian\u00e7a para um ou mais par\u00e2metros em um modelo de regress\u00e3o ajustado.<\/span><\/p>\n<p> <span style=\"color: #000000;\">Esta fun\u00e7\u00e3o usa a seguinte sintaxe b\u00e1sica:<\/span><\/p>\n<p> <strong><span style=\"color: #000000;\">confint(objeto, parm, n\u00edvel=0,95)<\/span><\/strong><\/p>\n<p> <span style=\"color: #000000;\">Ouro:<\/span><\/p>\n<ul>\n<li> <span style=\"color: #000000;\"><strong>object<\/strong> : Nome do modelo de regress\u00e3o ajustado<\/span><\/li>\n<li> <span style=\"color: #000000;\"><strong>parm<\/strong> : Par\u00e2metros para os quais calcular o intervalo de confian\u00e7a (o padr\u00e3o \u00e9 tudo)<\/span><\/li>\n<li> <span style=\"color: #000000;\"><strong>n\u00edvel<\/strong> : n\u00edvel de confian\u00e7a a ser usado (o valor padr\u00e3o \u00e9 0,95)<\/span><\/li>\n<\/ul>\n<p> <span style=\"color: #000000;\">O exemplo a seguir mostra como usar esta fun\u00e7\u00e3o na pr\u00e1tica.<\/span><\/p>\n<h2> <span style=\"color: #000000;\"><strong>Exemplo: como usar a fun\u00e7\u00e3o confit() em R<\/strong><\/span><\/h2>\n<p> <span style=\"color: #000000;\">Suponha que temos o seguinte quadro de dados em R que mostra o n\u00famero de horas gastas estudando, o n\u00famero de exames pr\u00e1ticos realizados e a nota do exame final de 10 alunos em uma turma:<\/span><\/p>\n<pre style=\"background-color: #ececec; font-size: 15px;\"> <strong><span style=\"color: #008080;\">#create data frame\n<\/span>df &lt;- data. <span style=\"color: #3366ff;\">frame<\/span> (score=c(77, 79, 84, 85, 88, 99, 95, 90, 92, 94),\n                 hours=c(1, 1, 2, 3, 2, 4, 4, 2, 3, 3),\n                 prac_exams=c(2, 3, 3, 2, 4, 5, 4, 3, 5, 4))\n\n<span style=\"color: #008080;\">#view data frame\n<\/span>df\n\n   score hours prac_exams\n1 77 1 2\n2 79 1 3\n3 84 2 3\n4 85 3 2\n5 88 2 4\n6 99 4 5\n7 95 4 4\n8 90 2 3\n9 92 3 5\n10 94 3 4\n<\/strong><\/pre>\n<p> <span style=\"color: #000000;\">Agora suponha que queiramos ajustar o seguinte modelo de regress\u00e3o linear m\u00faltipla em R:<\/span><\/p>\n<p> <span style=\"color: #000000;\">Nota do exame = \u03b2 <sub>0<\/sub> + \u03b2 <sub>1<\/sub> (horas) + \u03b2 <sub>2<\/sub> (exames pr\u00e1ticos)<\/span><\/p>\n<p> <span style=\"color: #000000;\">Podemos usar a fun\u00e7\u00e3o <a href=\"https:\/\/statorials.org\/pt\/funcao-lm-em-r\/\" target=\"_blank\" rel=\"noopener\">lm()<\/a> para adaptar este modelo:<\/span><\/p>\n<pre style=\"background-color: #ececec; font-size: 15px;\"> <strong><span style=\"color: #008080;\">#fit multiple linear regression model\n<\/span>fit &lt;- lm(score ~ hours + prac_exams, data=df)\n\n<span style=\"color: #008080;\">#view summary of model\n<\/span>summary(fit)\n\nCall:\nlm(formula = score ~ hours + prac_exams, data = df)\n\nResiduals:\n    Min 1Q Median 3Q Max \n-2.4324 -1.2632 -0.8956 0.4316 5.1412 \n\nCoefficients:\n            Estimate Std. Error t value Pr(&gt;|t|)    \n(Intercept) 68.4029 2.8723 23.815 5.85e-08 ***\nhours 4.1912 0.9961 4.207 0.0040 ** \nprac_exams 2.6912 0.9961 2.702 0.0306 *  \n---\nSignificant. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1\n\nResidual standard error: 2.535 on 7 degrees of freedom\nMultiple R-squared: 0.9005, Adjusted R-squared: 0.8721 \nF-statistic: 31.68 on 2 and 7 DF, p-value: 0.0003107\n<\/strong><\/pre>\n<p> <span style=\"color: #000000;\">Observe que o resumo do modelo exibe os coeficientes de regress\u00e3o ajustados:<\/span><\/p>\n<ul>\n<li> <span style=\"color: #000000;\">Intercepta\u00e7\u00e3o = 68,4029<\/span><\/li>\n<li> <span style=\"color: #000000;\">horas = 4,1912<\/span><\/li>\n<li> <span style=\"color: #000000;\">exames_prac = 2,6912<\/span><\/li>\n<\/ul>\n<p> <span style=\"color: #000000;\">Para obter um intervalo de confian\u00e7a de 95% para cada um desses coeficientes, podemos usar a fun\u00e7\u00e3o <strong>confint()<\/strong> :<\/span><\/p>\n<pre style=\"background-color: #ececec; font-size: 15px;\"> <strong><span style=\"color: #008080;\">#calculate 95% confidence interval for each coefficient in model<\/span>\nconfined(fit)\n\n                 2.5% 97.5%\n(Intercept) 61.6111102 75.194772\nhours 1.8357237 6.546629\nprac_exams 0.3357237 5.046629\n<\/strong><\/pre>\n<p> <span style=\"color: #000000;\">O intervalo de confian\u00e7a de 95% para cada par\u00e2metro \u00e9 indicado:<\/span><\/p>\n<ul>\n<li> <span style=\"color: #000000;\">IC 95% para intercepta\u00e7\u00e3o = [61,61, 75,19]<\/span><\/li>\n<li> <span style=\"color: #000000;\">IC 95% para horas = [1,84, 6,55]<\/span><\/li>\n<li> <span style=\"color: #000000;\">IC 95% para exames_prac = [0,34, 5,05]<\/span><\/li>\n<\/ul>\n<p> <span style=\"color: #000000;\">Para calcular um intervalo de confian\u00e7a de 99%, basta alterar o valor do argumento <strong>de n\u00edvel<\/strong> :<\/span><\/p>\n<pre style=\"background-color: #ececec; font-size: 15px;\"> <strong><span style=\"color: #008080;\">#calculate 99% confidence interval for each coefficient in model\n<\/span>confint(fit, level= <span style=\"color: #008000;\">0.99<\/span> )\n\n                 0.5% 99.5%\n(Intercept) 58.3514926 78.454390\nhours 0.7052664 7.677087\nprac_exams -0.7947336 6.177087\n<\/strong><\/pre>\n<p> <span style=\"color: #000000;\">E para calcular apenas um intervalo de confian\u00e7a para um par\u00e2metro espec\u00edfico, basta especificar o coeficiente usando o argumento <strong>parm<\/strong> :<\/span><\/p>\n<pre style=\"background-color: #ececec; font-size: 15px;\"> <strong><span style=\"color: #008080;\">#calculate 99% confidence interval for hours\n<\/span>confint(fit, parm=' <span style=\"color: #ff0000;\">hours<\/span> ', level= <span style=\"color: #008000;\">0.99<\/span> )\n\n          0.5% 99.5%\nhours 0.7052664 7.677087\n<\/strong><\/pre>\n<p> <span style=\"color: #000000;\">Observe que o intervalo de confian\u00e7a de 99% \u00e9 mostrado apenas para a vari\u00e1vel horas.<\/span><\/p>\n<h2> <span style=\"color: #000000;\"><strong>Recursos adicionais<\/strong><\/span><\/h2>\n<p> <span style=\"color: #000000;\">Os tutoriais a seguir fornecem informa\u00e7\u00f5es adicionais sobre regress\u00e3o linear em R:<\/span><\/p>\n<p> <a href=\"https:\/\/statorials.org\/pt\/interpretar-a-saida-da-regressao-em-r\/\" target=\"_blank\" rel=\"noopener\">Como interpretar a sa\u00edda da regress\u00e3o em R<\/a><br \/> <a href=\"https:\/\/statorials.org\/pt\/regressao-linear-simples-em-r\/\" target=\"_blank\" rel=\"noopener\">Como realizar regress\u00e3o linear simples em R<\/a><br \/> <a href=\"https:\/\/statorials.org\/pt\/regressao-linear-multipla-r\/\" target=\"_blank\" rel=\"noopener\">Como realizar regress\u00e3o linear m\u00faltipla em R<\/a><br \/> Como realizar regress\u00e3o log\u00edstica em R<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Voc\u00ea pode usar a fun\u00e7\u00e3o confint() em R para calcular um intervalo de confian\u00e7a para um ou mais par\u00e2metros em um modelo de regress\u00e3o ajustado. Esta fun\u00e7\u00e3o usa a seguinte sintaxe b\u00e1sica: confint(objeto, parm, n\u00edvel=0,95) Ouro: object : Nome do modelo de regress\u00e3o ajustado parm : Par\u00e2metros para os quais calcular o intervalo de confian\u00e7a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-3902","post","type-post","status-publish","format-standard","hentry","category-guia"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v21.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Como usar a fun\u00e7\u00e3o confint() em R - Estatologia<\/title>\n<meta name=\"description\" content=\"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/statorials.org\/pt\/cristalizado-r\/\" \/>\n<meta property=\"og:locale\" content=\"pt_PT\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Como usar a fun\u00e7\u00e3o confint() em R - Estatologia\" \/>\n<meta property=\"og:description\" content=\"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/statorials.org\/pt\/cristalizado-r\/\" \/>\n<meta property=\"og:site_name\" content=\"Statorials\" \/>\n<meta property=\"article:published_time\" content=\"2023-07-14T21:02:11+00:00\" \/>\n<meta name=\"author\" content=\"Dr. benjamim anderson\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Escrito por\" \/>\n\t<meta name=\"twitter:data1\" content=\"Dr. benjamim anderson\" \/>\n\t<meta name=\"twitter:label2\" content=\"Tempo estimado de leitura\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutos\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/statorials.org\/pt\/cristalizado-r\/\",\"url\":\"https:\/\/statorials.org\/pt\/cristalizado-r\/\",\"name\":\"Como usar a fun\u00e7\u00e3o confint() em R - Estatologia\",\"isPartOf\":{\"@id\":\"https:\/\/statorials.org\/pt\/#website\"},\"datePublished\":\"2023-07-14T21:02:11+00:00\",\"dateModified\":\"2023-07-14T21:02:11+00:00\",\"author\":{\"@id\":\"https:\/\/statorials.org\/pt\/#\/schema\/person\/e08f98e8db95e0aa9c310e1b27c9c666\"},\"description\":\"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.\",\"breadcrumb\":{\"@id\":\"https:\/\/statorials.org\/pt\/cristalizado-r\/#breadcrumb\"},\"inLanguage\":\"pt-PT\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/statorials.org\/pt\/cristalizado-r\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/statorials.org\/pt\/cristalizado-r\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Lar\",\"item\":\"https:\/\/statorials.org\/pt\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Como usar a fun\u00e7\u00e3o confit() em r\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/statorials.org\/pt\/#website\",\"url\":\"https:\/\/statorials.org\/pt\/\",\"name\":\"Statorials\",\"description\":\"O seu guia para a literacia estat\u00edstica!\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/statorials.org\/pt\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"pt-PT\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/statorials.org\/pt\/#\/schema\/person\/e08f98e8db95e0aa9c310e1b27c9c666\",\"name\":\"Dr. benjamim anderson\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"pt-PT\",\"@id\":\"https:\/\/statorials.org\/pt\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/statorials.org\/pt\/wp-content\/uploads\/2023\/10\/Dr.-Benjamin-Anderson-96x96.jpg\",\"contentUrl\":\"https:\/\/statorials.org\/pt\/wp-content\/uploads\/2023\/10\/Dr.-Benjamin-Anderson-96x96.jpg\",\"caption\":\"Dr. benjamim anderson\"},\"description\":\"Ol\u00e1, sou Benjamin, um professor aposentado de estat\u00edstica que se tornou professor dedicado na Statorials. Com vasta experi\u00eancia e conhecimento na \u00e1rea de estat\u00edstica, estou empenhado em compartilhar meu conhecimento para capacitar os alunos por meio de Statorials. Saber mais\",\"sameAs\":[\"https:\/\/statorials.org\/pt\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Como usar a fun\u00e7\u00e3o confint() em R - Estatologia","description":"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/statorials.org\/pt\/cristalizado-r\/","og_locale":"pt_PT","og_type":"article","og_title":"Como usar a fun\u00e7\u00e3o confint() em R - Estatologia","og_description":"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.","og_url":"https:\/\/statorials.org\/pt\/cristalizado-r\/","og_site_name":"Statorials","article_published_time":"2023-07-14T21:02:11+00:00","author":"Dr. benjamim anderson","twitter_card":"summary_large_image","twitter_misc":{"Escrito por":"Dr. benjamim anderson","Tempo estimado de leitura":"2 minutos"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/statorials.org\/pt\/cristalizado-r\/","url":"https:\/\/statorials.org\/pt\/cristalizado-r\/","name":"Como usar a fun\u00e7\u00e3o confint() em R - Estatologia","isPartOf":{"@id":"https:\/\/statorials.org\/pt\/#website"},"datePublished":"2023-07-14T21:02:11+00:00","dateModified":"2023-07-14T21:02:11+00:00","author":{"@id":"https:\/\/statorials.org\/pt\/#\/schema\/person\/e08f98e8db95e0aa9c310e1b27c9c666"},"description":"Este tutorial explica como usar a fun\u00e7\u00e3o confint() em R para criar intervalos de confian\u00e7a para os par\u00e2metros de um modelo de regress\u00e3o.","breadcrumb":{"@id":"https:\/\/statorials.org\/pt\/cristalizado-r\/#breadcrumb"},"inLanguage":"pt-PT","potentialAction":[{"@type":"ReadAction","target":["https:\/\/statorials.org\/pt\/cristalizado-r\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/statorials.org\/pt\/cristalizado-r\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Lar","item":"https:\/\/statorials.org\/pt\/"},{"@type":"ListItem","position":2,"name":"Como usar a fun\u00e7\u00e3o confit() em r"}]},{"@type":"WebSite","@id":"https:\/\/statorials.org\/pt\/#website","url":"https:\/\/statorials.org\/pt\/","name":"Statorials","description":"O seu guia para a literacia estat\u00edstica!","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/statorials.org\/pt\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"pt-PT"},{"@type":"Person","@id":"https:\/\/statorials.org\/pt\/#\/schema\/person\/e08f98e8db95e0aa9c310e1b27c9c666","name":"Dr. benjamim anderson","image":{"@type":"ImageObject","inLanguage":"pt-PT","@id":"https:\/\/statorials.org\/pt\/#\/schema\/person\/image\/","url":"https:\/\/statorials.org\/pt\/wp-content\/uploads\/2023\/10\/Dr.-Benjamin-Anderson-96x96.jpg","contentUrl":"https:\/\/statorials.org\/pt\/wp-content\/uploads\/2023\/10\/Dr.-Benjamin-Anderson-96x96.jpg","caption":"Dr. benjamim anderson"},"description":"Ol\u00e1, sou Benjamin, um professor aposentado de estat\u00edstica que se tornou professor dedicado na Statorials. Com vasta experi\u00eancia e conhecimento na \u00e1rea de estat\u00edstica, estou empenhado em compartilhar meu conhecimento para capacitar os alunos por meio de Statorials. Saber mais","sameAs":["https:\/\/statorials.org\/pt"]}]}},"yoast_meta":{"yoast_wpseo_title":"","yoast_wpseo_metadesc":"","yoast_wpseo_canonical":""},"_links":{"self":[{"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/posts\/3902","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/comments?post=3902"}],"version-history":[{"count":0,"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/posts\/3902\/revisions"}],"wp:attachment":[{"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/media?parent=3902"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/categories?post=3902"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/statorials.org\/pt\/wp-json\/wp\/v2\/tags?post=3902"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}