Regression Analysis

Note: Input values must be separated by tabs. Copy and paste from Excel/Numbers.

Please make sure that your data includes the header (variable names) in the first row.
The outcome (dependent) variable should be placed in the first column.


                
                

Basic statistics


                

Correlation


                
Scatter plot matrices

Regression analysis


                

Choose a model by AIC in a Stepwise Algorithm


                

R session info

              
Note

This web application is developed with Shiny.


List of Packages Used
library(shiny)
library(shinyAce)
library(psych)
library(car)

Code

Source code for this application is based on "The handbook of Research in Foreign Language Learning and Teaching" (Takeuchi & Mizumoto, 2012).

The code for this web application is available at GitHub.

If you want to run this code on your computer (in a local R session), run the code below:
library(shiny)
runGitHub("reg","mizumot")


Citation in Publications

Mizumoto, A. (2015). Langtest (Version 1.0) [Web application]. Retrieved from http://langtest.jp


Article

Mizumoto, A., & Plonsky, L. (2015). R as a lingua franca: Advantages of using R for quantitative research in applied linguistics. Applied Linguistics, Advance online publication. doi:10.1093/applin/amv025


Recommended

To learn more about R, I suggest this excellent and free e-book (pdf), A Guide to Doing Statistics in Second Language Research Using R, written by Dr. Jenifer Larson-Hall.

Also, if you are a cool Mac user and want to use R with GUI, MacR is defenitely the way to go!


Author

Atsushi MIZUMOTO, Ph.D.
Associate Professor of Applied Linguistics
Faculty of Foreign Language Studies /
Graduate School of Foreign Language Education and Research,
Kansai University, Osaka, Japan



Code for "Regression Analysis"
by Atsushi Mizumoto

show with app
library(shiny)
library(shinyAce)
library(psych)
library(car)


shinyServer(function(input, output) {


    bs <- reactive({
            x <- read.csv(text=input$text, sep="\t")
            describe(x)[2:13]
    })
    
    
    correl <- reactive({
            x <- read.csv(text=input$text, sep="\t")
            
            round(cor(cbind(x), use = "complete"),3)
    })
    
    
    
    makecorPlot <- function(){
        x <- read.csv(text=input$text, sep="\t")
        pairs.panels(x)
    }
    
    output$corPlot <- renderPlot({
        print(makecorPlot())
    })
    
    
    
    reg <- reactive({
        dat <- read.csv(text=input$text, sep="\t")
        
        colnames(dat) <- c("Outcome", c(colnames(dat)[2:ncol(dat)]))
        result <- lm(Outcome ~., dat)
        
        reslt <- summary(result)
        print(reslt)
        cnfi <- confint(result)
        
        cat("---", "\n", "95% CI of B (Unstandardized beta):", "\n")
        print(cnfi)
        
        z <- scale(dat)     # standardize the data
        z <- data.frame(z)
        z.res <- summary(lm(Outcome ~ ., z))
        
        stdb <- data.frame(round((z.res$coefficients[,1][-1]),3))
        colnames(stdb)[1] <- "Standardized beta"
        
        cat("\n", "---", "\n", "Standardized beta estimates:", "\n")
        print(stdb)
        
    if (ncol(dat) >= 3) {

        VIF <- vif(result)
        Tolerance <- 1/VIF
        
        vif.res <- round(data.frame(VIF, Tolerance),3)
        
        cat("\n", "---", "\n", "VIF and tolerance statistic (1/VIF):", "\n")
        print(vif.res)
        cat("\n", "VIF should be smaller than 10 (clozer to 1 better);", "\n",
        "tolerance statistic (1/VIF) should be greater than 0.2.", "\n")
    }
    })
    
    
    
    aic <- reactive({
        dat <- read.csv(text=input$text, sep="\t")
        
        colnames(dat) <- c("Outcome", c(colnames(dat)[2:ncol(dat)]))
        result <- lm(Outcome ~., dat)
        
        model <- step(result)
        print(model)
        
        cat("\n", "---", "\n", "Regression analysis with the best fitting model:", "\n")
        
        summary(model)
        
    })
    
    
    info <- reactive({
        info1 <- paste("This analysis was conducted with ", strsplit(R.version$version.string, " \\(")[[1]][1], ".", sep = "")# バージョン情報
        info2 <- paste("It was executed on ", date(), ".", sep = "")# 実行日時
        cat(sprintf(info1), "\n")
        cat(sprintf(info2), "\n")
    })
    
    output$info.out <- renderPrint({
        info()
    })



    output$textarea.out <- renderPrint({
        bs()
    })

    output$correl.out <- renderPrint({
        correl()
    })
    
    output$reg.out <- renderPrint({
        reg()
    })
    
    output$aic.out <- renderPrint({
        aic()
    })
    
   

})
library(shiny)
library(shinyAce)


shinyUI(bootstrapPage(

   headerPanel("Regression Analysis"),

   mainPanel(
        tabsetPanel(

        tabPanel("Main",

        p('Note: Input values must be separated by tabs. Copy and paste from Excel/Numbers.'),

        p(HTML("<b><div style='background-color:#FADDF2;border:1px solid black;'>Please make sure that your data includes the header (variable names) in the first row.<br>
                The outcome (dependent) variable should be placed in the first column.</b></div>")),

            aceEditor("text", value="TOEIC\tVocabulary\tGrammar\tPronunciation\n275\t21\t35\t53\n175\t21\t29\t0\n535\t37\t56\t60\n10\t3\t4\t55\n385\t14\t36\t62\n655\t44\t47\t62\n335\t9\t2\t77\n630\t3\t46\t81\n605\t34\t44\t67\n530\t18\t35\t82\n645\t42\t45\t53\n440\t25\t35\t59\n750\t24\t57\t79\n610\t28\t52\t73\n830\t55\t44\t66\n600\t22\t50\t44\n760\t63\t30\t73\n300\t14\t33\t77\n340\t22\t0\t59\n585\t25\t73\t52\n475\t34\t32\t74\n215\t10\t32\t73\n150\t1\t31\t71\n655\t39\t17\t56\n710\t10\t73\t68\n360\t34\t12\t62\n350\t9\t37\t77\n540\t27\t55\t82\n710\t36\t52\t51\n310\t10\t19\t87\n655\t41\t53\t74\n500\t32\t59\t55\n115\t19\t29\t63\n615\t32\t58\t88\n400\t11\t16\t57\n440\t27\t28\t46\n555\t24\t30\t71\n625\t32\t51\t80\n345\t22\t31\t45\n670\t44\t7\t63\n565\t47\t32\t62\n595\t35\t43\t63\n585\t67\t61\t75\n415\t5\t40\t58\n620\t27\t80\t66\n175\t6\t64\t23\n790\t53\t64\t66\n450\t38\t18\t61\n750\t39\t41\t70\n665\t48\t62\t80\n700\t11\t82\t91\n585\t34\t53\t81\n380\t19\t48\t76\n680\t61\t50\t86\n315\t41\t45\t68\n330\t15\t32\t67\n645\t42\t56\t66\n180\t11\t4\t34\n835\t79\t64\t45\n550\t40\t45\t70\n340\t23\t40\t62\n805\t45\t85\t87\n615\t42\t92\t56\n815\t62\t44\t71\n610\t10\t59\t53\n720\t58\t55\t50\n525\t45\t43\t55\n575\t48\t49\t74\n570\t6\t43\t62\n420\t22\t22\t73\n395\t24\t44\t73\n280\t35\t33\t86\n945\t66\t56\t68\n880\t60\t73\t72\n290\t8\t13\t48\n420\t12\t2\t66\n950\t50\t59\t67\n435\t27\t46\t79\n605\t18\t60\t78\n170\t1\t47\t12\n940\t60\t70\t63\n260\t11\t35\t73\n335\t7\t34\t78\n270\t9\t60\t45\n670\t45\t39\t70\n860\t59\t100\t72\n835\t68\t36\t73\n850\t61\t58\t68\n405\t9\t55\t53\n500\t25\t34\t65\n490\t20\t32\t49\n515\t28\t72\t64\n950\t89\t47\t63\n425\t4\t37\t73\n430\t12\t28\t73\n695\t36\t55\t64\n150\t11\t28\t80\n355\t12\t41\t81\n785\t39\t62\t74\n250\t31\t26\t61\n560\t12\t45\t75\n425\t6\t14\t60\n455\t39\t20\t65\n815\t59\t62\t92\n715\t51\t85\t74\n270\t17\t44\t65\n395\t8\t30\t78\n210\t8\t33\t20\n705\t30\t50\t89\n250\t23\t1\t69\n665\t45\t54\t69\n440\t26\t29\t70\n805\t55\t74\t97\n180\t9\t21\t82\n795\t77\t53\t66\n605\t29\t47\t76\n280\t10\t19\t69\n605\t8\t57\t75\n250\t5\t11\t33\n525\t33\t63\t58\n570\t43\t29\t59\n535\t2\t64\t66\n425\t39\t12\t71\n330\t18\t82\t70\n555\t10\t43\t72\n550\t34\t29\t71\n870\t51\t59\t62\n550\t18\t17\t45\n840\t49\t66\t84\n665\t67\t41\t54\n210\t18\t31\t84\n405\t13\t41\t91\n585\t22\t31\t92\n520\t17\t67\t75\n585\t35\t55\t57\n390\t21\t31\t59\n830\t69\t37\t88\n400\t10\t23\t72\n240\t11\t31\t38\n275\t12\t29\t64\n340\t18\t51\t61\n105\t21\t15\t34\n615\t8\t39\t65\n175\t14\t33\t38\n425\t25\t56\t72\n275\t10\t35\t60\n475\t27\t28\t48\n765\t32\t53\t80\n810\t51\t84\t50\n825\t51\t64\t73\n795\t35\t54\t68\n585\t37\t56\t64\n610\t26\t47\t81\n595\t49\t28\t72\n490\t5\t75\t65\n880\t78\t49\t97\n605\t4\t59\t57\n765\t35\t31\t72\n650\t52\t35\t57\n430\t23\t50\t78\n625\t26\t52\t74\n700\t13\t61\t77\n585\t25\t59\t70\n895\t100\t70\t100\n190\t1\t57\t68\n460\t25\t34\t70\n680\t68\t17\t75\n915\t69\t69\t66\n120\t1\t20\t84\n150\t29\t30\t57\n265\t12\t37\t55\n275\t0\t3\t62\n935\t67\t58\t80\n700\t25\t51\t69\n750\t48\t52\t70\n430\t45\t19\t61\n240\t8\t6\t74\n660\t35\t66\t69\n405\t10\t40\t79\n950\t57\t65\t82\n660\t18\t37\t74\n425\t36\t15\t64\n615\t32\t81\t69\n355\t23\t24\t69\n550\t48\t21\t77\n635\t32\t73\t78\n190\t28\t29\t16\n170\t32\t16\t54\n125\t6\t41\t78\n410\t6\t31\t62\n715\t68\t44\t85\n990\t88\t55\t49\n785\t58\t40\t75\n320\t12\t51\t65\n890\t78\t53\t47\n565\t38\t38\t66\n525\t11\t73\t55\n730\t11\t67\t73\n750\t53\t49\t74\n565\t69\t51\t79",
                mode="r", theme="terminal"),

            br(),

            h3("Basic statistics"),
            verbatimTextOutput("textarea.out"),

            br(),

            h3("Correlation"),

            verbatimTextOutput("correl.out"),

            br(),

            strong("Scatter plot matrices"),
            br(),

            plotOutput("corPlot"),

            br(),

            h3("Regression analysis"),
            verbatimTextOutput("reg.out"),

            br(),

            h3("Choose a model by AIC in a Stepwise Algorithm"),
            verbatimTextOutput("aic.out"),

            br(),
            br(),

            strong('R session info'),
            verbatimTextOutput("info.out")


            ),


        tabPanel("About",

            strong('Note'),
            p('This web application is developed with',
            a("Shiny.", href="http://www.rstudio.com/shiny/", target="_blank"),
            ''),

            br(),

            strong('List of Packages Used'), br(),
            code('library(shiny)'),br(),
            code('library(shinyAce)'),br(),
            code('library(psych)'),br(),
            code('library(car)'),br(),

            br(),

            strong('Code'),
            p('Source code for this application is based on',
            a('"The handbook of Research in Foreign Language Learning and Teaching" (Takeuchi & Mizumoto, 2012).', href='http://mizumot.com/handbook/', target="_blank")),

            p('The code for this web application is available at',
            a('GitHub.', href='https://github.com/mizumot/reg', target="_blank")),

            p('If you want to run this code on your computer (in a local R session), run the code below:',
            br(),
            code('library(shiny)'),br(),
            code('runGitHub("reg","mizumot")')
            ),

            br(),

            strong('Citation in Publications'),
            p('Mizumoto, A. (2015). Langtest (Version 1.0) [Web application]. Retrieved from http://langtest.jp'),

            br(),

            strong('Article'),
            p('Mizumoto, A., & Plonsky, L. (2015).', a("R as a lingua franca: Advantages of using R for quantitative research in applied linguistics.", href='http://applij.oxfordjournals.org/content/early/2015/06/24/applin.amv025.abstract', target="_blank"), em('Applied Linguistics,'), 'Advance online publication. doi:10.1093/applin/amv025'),

            br(),

            strong('Recommended'),
            p('To learn more about R, I suggest this excellent and free e-book (pdf),',
            a("A Guide to Doing Statistics in Second Language Research Using R,", href="http://cw.routledge.com/textbooks/9780805861853/guide-to-R.asp", target="_blank"),
            'written by Dr. Jenifer Larson-Hall.'),

            p('Also, if you are a cool Mac user and want to use R with GUI,',
            a("MacR", href="http://www.urano-ken.com/blog/2013/02/25/installing-and-using-macr/", target="_blank"),
            'is defenitely the way to go!'),

            br(),

            strong('Author'),
            p(a("Atsushi MIZUMOTO,", href="http://mizumot.com", target="_blank"),' Ph.D.',br(),
            'Associate Professor of Applied Linguistics',br(),
            'Faculty of Foreign Language Studies /',br(),
            'Graduate School of Foreign Language Education and Research,',br(),
            'Kansai University, Osaka, Japan'),

            br(),

            a(img(src="http://i.creativecommons.org/p/mark/1.0/80x15.png"), target="_blank", href="http://creativecommons.org/publicdomain/mark/1.0/"),

            p(br())

            )

))
))
Code license: GPL-3