Differences

This shows you the differences between two versions of the page.

--- regression [2019/05/13 08:57] – hkimscil
+++ regression [2019/05/20 08:50] – [e.g. Simple Regression] hkimscil
@@ Line 351: / Line 351: @@
-====== E.g., 2. Simple regression ======
+====== E.g., Simple regression ======
 data:
 {{:acidity.sav}} \\
@@ Line 588: / Line 588: @@
  SS<sub>total</sub> = 87.733
  r<sup>2</sup> = SS<sub>reg</sub> / SS<sub>total</sub> = 42.462 / 87.733 = .484.
+====== e.g. Simple Regression ======
+{{:AllenMursau.data.csv}}
+<code>datavar <- read.csv("http://commres.net/wiki/_media/allenmursau.data.csv")
+</code>
+<code>> mod <- lm(Y ~ X, data=datavar)
+> summary(mod)
+Call:
+lm(formula = Y ~ X, data = datavar)
+Residuals:
+    Min      1Q  Median      3Q     Max
+-250.22 -132.28   33.09  165.53  187.78
+Coefficients:
+            Estimate Std. Error t value Pr(>|t|)
+(Intercept)  300.976    229.754   1.310    0.219
+X             10.312      3.124   3.301    0.008 **
+---
+Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
+Residual standard error: 170.5 on 10 degrees of freedom
+Multiple R-squared:  0.5214,	Adjusted R-squared:  0.4736
+F-statistic:  10.9 on 1 and 10 DF,  p-value: 0.008002
+</code>
+<code>> anova(mod)
+Analysis of Variance Table
+Response: Y
+          Df Sum Sq Mean Sq F value   Pr(>F)
+X          1 316874  316874  10.896 0.008002 **
+Residuals 10 290824   29082
+---
+Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
+> </code>
+<code>
+> ss_total <- var(datavar$Y)*11
+> round(ss_total)
+[1] 607698
+> 316874 + 290824  # 위의 아웃풋에서 Sum Sq for X와 Residuals를 더한 값
+[1] 607698
+</code>
+<WRAP box help>위의 anova 아웃풋 박스에서 R square value를 구할 수 있는가?
+</WRAP>
 ====== E.g., 3. Simple regression: Adjusted R squared & Slope test ======