couple <- read.table("C:/Rexamples/coupledata.txt", header=T)
View(couple)
summary(couple)
attach(couple)
hgtdif <- hushgt - wifehgt
summary(hgtdif)
boxplot(hgtdif)
stem(hgtdif)
qqnorm(hgtdif)
qqline(hgtdif)
shapiro.test(hgtdif)
t.test(hgtdif)
t.test(hgtdif, mu = 100)
t.test(hushgt, wifehgt, paired=TRUE)


--------------------- NOTE ------------------------

The first line above which reads the data from the file
"coupledata.txt" assumes that this file is in the directory
"C:/Rexamples".  Obey this convention or modify the command.

-------------------------- results ----------------------------------

The boxplot and normal probability plot (qqplot) requested in this
program will appear in the plot window of RStudio.  They can be saved
as pdfs or images. I have not posted them here.  These plots are
somewhat crude since I did not specify titles, labels, or such.

The remainder of this file is copied and pasted from the RStudio
command window.

--------------------------------------------------------

> couple <- read.table("C:/Rexamples/coupledata.txt", header=T)
> View(couple)
> summary(couple)
     couple       husbage          hushgt        wifeage
 Min.   :  1   Min.   :20.00   Min.   :1559   Min.   :18.00
 1st Qu.: 43   1st Qu.:33.00   1st Qu.:1691   1st Qu.:32.00
 Median : 85   Median :43.00   Median :1725   Median :41.00
 Mean   : 85   Mean   :42.85   Mean   :1733   Mean   :40.61
 3rd Qu.:127   3rd Qu.:53.00   3rd Qu.:1774   3rd Qu.:50.00
 Max.   :169   Max.   :64.00   Max.   :1905   Max.   :64.00
    wifehgt          age
 Min.   :1410   Min.   :17.00
 1st Qu.:1560   1st Qu.:22.00
 Median :1600   Median :24.00
 Mean   :1603   Mean   :25.22
 3rd Qu.:1650   3rd Qu.:27.00
 Max.   :1760   Max.   :52.00
> attach(couple)
The following object is masked _by_ .GlobalEnv:

    couple
> hgtdif <- hushgt - wifehgt
> summary(hgtdif)
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
  -96.0    81.0   130.0   129.8   181.0   303.0
> boxplot(hgtdif)
> stem(hgtdif)

  The decimal point is 1 digit(s) to the right of the |

   -8 | 6
   -6 | 5
   -4 | 6
   -2 | 7001
   -0 | 2
    0 | 00193459
    2 | 45569
    4 | 00569
    6 | 0055680011345599
    8 | 1344455804456
   10 | 033500334589
   12 | 0033335555588890003455559
   14 | 0114455550155599
   16 | 00001145556904558
   18 | 01338900134555666
   20 | 459059
   22 | 58893569
   24 | 13460589
   26 | 16
   28 | 15
   30 | 3

> qqnorm(hgtdif)
> qqline(hgtdif)
> shapiro.test(hgtdif)

    Shapiro-Wilk normality test

data:  hgtdif
W = 0.9921, p-value = 0.4787

> t.test(hgtdif)

    One Sample t-test

data:  hgtdif
t = 22.2003, df = 168, p-value < 2.2e-16
alternative hypothesis: true mean is not equal to 0
95 percent confidence interval:
 118.2779 141.3671
sample estimates:
mean of x
 129.8225

> t.test(hgtdif, mu = 100)

    One Sample t-test

data:  hgtdif
t = 5.0998, df = 168, p-value = 9.098e-07
alternative hypothesis: true mean is not equal to 100
95 percent confidence interval:
 118.2779 141.3671
sample estimates:
mean of x
 129.8225

> t.test(hushgt, wifehgt, paired=TRUE)

    Paired t-test

data:  hushgt and wifehgt
t = 22.2003, df = 168, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 118.2779 141.3671
sample estimates:
mean of the differences
               129.8225

>