PROGRAM 1

data iron;

input fe3 fe4;

cards;

0.71 2.20

1.66 2.69

2.01 3.54

2.16 3.75

2.42 3.83

2.42 4.08

2.56 4.27

2.60 4.53

3.31 5.32

3.64 6.18

3.74 6.22

3.74 6.33

4.39 6.97

4.50 6.97

5.07 7.52

5.26 8.36

8.15 11.65

8.24 12.45

;

data iron; set iron;

diff=fe3-fe4;

run;

proc ttest;

var diff;

run;

The TTEST Procedure

Statistics

Lower CL Upper CL Lower CL Upper CL

Variable N Mean Mean Mean Std Dev Std Dev Std Dev Std Err

diff 18 -2.64 -2.238 -1.836 0.6063 0.808 1.2113 0.1905

T-Tests

Variable DF t Value Pr > |t|

diff 17 -11.75 <.0001

PROGRAM 2

data iron;

input irontype percent;

cards;

3 0.71

3 1.66

3 2.01

3 2.16

3 2.42

3 2.42

3 2.56

3 2.60

3 3.31

3 3.64

3 3.74

3 3.74

3 4.39

3 4.50

3 5.07

3 5.26

3 8.15

3 8.24

4 2.20

4 2.69

4 3.54

4 3.75

4 3.83

4 4.08

4 4.27

4 4.53

4 5.32

4 6.18

4 6.22

4 6.33

4 6.97

4 6.97

4 7.52

4 8.36

4 11.65

4 12.45

;

proc ttest;

var percent;

class irontype;

run;

The TTEST Procedure

Statistics

Lower CL Upper CL Lower CL Upper CL

Variable Class N Mean Mean Mean Std Dev Std Dev Std Dev Std Err

percent 3 18 2.689 3.6989 4.7088 1.5239 2.0309 3.0446 0.4787

percent 4 18 4.5409 5.9367 7.3324 2.1062 2.8068 4.2078 0.6616

percent Diff (1-2) -3.897 -2.238 -0.578 1.9815 2.4497 3.2097 0.8166

T-Tests

Variable Method Variances DF t Value Pr > |t|

percent Pooled Equal 34 -2.74 0.0097

percent Satterthwaite Unequal 31 -2.74 0.0101

Equality of Variances

Variable Method Num DF Den DF F Value Pr > F

percent Folded F 17 17 1.91 0.1924