Example 2.B.1 from Generalized Linear Mixed Models: Modern Concepts, Methods and Applications by Walter W. Stroup(p-53)
Source:R/Exam2.B.1.R
Exam2.B.1.Rd
Exam2.B.1 is used to visualize the effect of lm model statement with Gaussian data and their design matrix
References
Stroup, W. W. (2012). Generalized Linear Mixed Models: Modern Concepts, Methods and Applications. CRC Press.
Author
Muhammad Yaseen (myaseen208@gmail.com)
Adeela Munawar (adeela.uaf@gmail.com)
Examples
#-----------------------------------------------------------------------------------
## Linear Model discussed in Example 2.B.1 using simple regression data of Table1.1
#-----------------------------------------------------------------------------------
data(Table1.1)
Exam2.B.1.lm1 <- lm(formula = y~x, data = Table1.1)
summary(Exam2.B.1.lm1)
#>
#> Call:
#> lm(formula = y ~ x, data = Table1.1)
#>
#> Residuals:
#> Min 1Q Median 3Q Max
#> -4.0909 -0.9727 -0.2182 0.8364 4.3455
#>
#> Coefficients:
#> Estimate Std. Error t value Pr(>|t|)
#> (Intercept) -1.2727 1.4066 -0.905 0.389136
#> x 1.4364 0.2378 6.041 0.000193 ***
#> ---
#> Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
#>
#> Residual standard error: 2.494 on 9 degrees of freedom
#> Multiple R-squared: 0.8022, Adjusted R-squared: 0.7802
#> F-statistic: 36.5 on 1 and 9 DF, p-value: 0.0001925
#>
library(parameters)
model_parameters(Exam2.B.1.lm1)
#> Parameter | Coefficient | SE | 95% CI | t(9) | p
#> -----------------------------------------------------------------
#> (Intercept) | -1.27 | 1.41 | [-4.45, 1.91] | -0.90 | 0.389
#> x | 1.44 | 0.24 | [ 0.90, 1.97] | 6.04 | < .001
#>
#> Uncertainty intervals (equal-tailed) and p-values (two-tailed) computed
#> using a Wald t-distribution approximation.
DesignMatrix.lm1 <- model.matrix (object = Exam2.B.1.lm1)
DesignMatrix.lm1
#> (Intercept) x
#> 1 1 0
#> 2 1 1
#> 3 1 2
#> 4 1 3
#> 5 1 4
#> 6 1 5
#> 7 1 6
#> 8 1 7
#> 9 1 8
#> 10 1 9
#> 11 1 10
#> attr(,"assign")
#> [1] 0 1