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Samuel Kaiser

2026-02-20

## Loading required package: splines

## Loading required package: RcmdrMisc

## Loading required package: car

## Loading required package: carData

## Loading required package: sandwich

## Loading required package: effects

## lattice theme set by effectsTheme()
## See ?effectsTheme for details.

## The Commander GUI is launched only in interactive sessions

## 
## Attaching package: 'Rcmdr'

## The following object is masked from 'package:base':
## 
##     errorCondition

> Waterquality <- readXL("D:/KNUST/MPhil/Math and Statistics/water_quality.xlsx", rownames=FALSE, header=TRUE, na="",
+    sheet="dataset", stringsAsFactors=TRUE)

> library(abind, pos=16)

> library(e1071, pos=17)

Numerical Summaries: Waterquality

> numSummary(Waterquality[,"Result", drop=FALSE], statistics=c("mean", "sd", "IQR", "quantiles", "cv", "skewness", 
+   "kurtosis"), quantiles=c(0,.25,.5,.75,1), type="2")

Warning in cv(X): not all values are positive

      mean        sd IQR       cv skewness kurtosis 0% 25% 50% 75% 100%    n
 0.2707836 0.6684707 0.2 2.468653 6.806795 62.47219  0   0 0.1 0.2  8.8 2422

Numerical Summaries: Waterquality

> numSummary(Waterquality[,"Result", drop=FALSE], groups=Waterquality$Suburb, statistics=c("mean", "sd", "IQR", 
+   "quantiles", "cv", "skewness", "kurtosis"), quantiles=c(0,.25,.5,.75,1), type="2")

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

Warning in FUN(X[[i]], ...): CV is deprecated in RcmdrMisc package. Use cv
instead.

Warning in cv(x = x, na.rm = na.rm): not all values are positive

                 mean        sd    IQR       cv skewness   kurtosis 0% 25%  50%
Blancathey  0.5063170 1.1641068 0.5425 2.299166 4.512782 22.8617883  0   0 0.10
Hallburgh   0.1711608 0.3124392 0.2000 1.825414 3.856363 22.7375533  0   0 0.06
Merton      0.1625438 0.2909154 0.2000 1.789766 3.350119 12.9699630  0   0 0.06
Southwold   0.1550895 0.2329508 0.2000 1.502042 2.331046  5.5812579  0   0 0.07
Swadlincote 0.1611268 0.1965144 0.2000 1.219625 1.562331  2.0282953  0   0 0.10
Tarnstead   0.3475811 1.0499743 0.2000 3.020804 5.012955 28.2948705  0   0 0.07
Wakefield   0.3796176 0.5591376 0.5500 1.472897 1.446995  0.6723909  0   0 0.10
               75% 100% Result:n
Blancathey  0.5425 8.01      336
Hallburgh   0.2000 3.00      339
Merton      0.2000 2.00      343
Southwold   0.2000 1.25      339
Swadlincote 0.2000 0.91      339
Tarnstead   0.2000 8.80      339
Wakefield   0.5500 2.04      387

Histogram: Result

> with(Waterquality, Hist(Result, scale="frequency", breaks="Sturges", col="darkgray"))

Histogram: Result

> with(Waterquality, Hist(Result, groups=Suburb, scale="frequency", breaks="Sturges", col="darkgray"))

Boxplot: ~ Result

> Boxplot( ~ Result, data=Waterquality, id=list(method="y"))

 [1] "1299" "541"  "697"  "1410" "860"  "324"  "907"  "672"  "2123" "1632"

Boxplot: Result ~ Suburb

> Boxplot(Result ~ Suburb, data=Waterquality, id=list(method="y"))

 [1] "697"  "1410" "860"  "324"  "907"  "2123" "1225" "1710" "768"  "995" 
[11] "202"  "1862" "262"  "1899" "313"  "293"  "365"  "421"  "338"  "375" 
[21] "199"  "2294" "2385" "1920" "2045" "1807" "1951" "2003" "1835" "2066"
[31] "268"  "297"  "305"  "2398" "550"  "459"  "2243" "506"  "2316" "570" 
[41] "1014" "2388" "2210" "229"  "2229" "274"  "2259" "2306" "246"  "1148"
[51] "1299" "541"  "672"  "1632" "43"   "266"  "2155" "800"  "1218" "206" 
[61] "195"  "320"  "803"  "1964" "723"  "2042" "617"  "446"  "529"  "1864"