1          ***********************************************;
2          *** Data from Freund & Wilson (1993)        ***;
3          *** TABLE 8.24 : ESTIMATING TREE WEIGHTS    ***;
4          ***********************************************;
5          options ps=256 ls=132 nocenter nodate nonumber;
6
7          data one; infile cards missover;
8              TITLE1 'EXST7015: Estimating tree weights from other morphometric variables';
9            input ObsNo Dbh Height Age Grav Weight ObsID $;
10         ********  label ObsNo  = 'Original observation number'
11                         Dbh    = 'Diameter at breast height (inches)'
12                         Height = 'Height of the tree (feet)'
13                         Age    = 'Age of the tree (years)'
14                         Grav   = 'Specific gravity of the wood'
15                         Weight = 'Harvest weight of the tree (lbs)'
16                         ObsId  = 'Identification letter added to dataset';
17            lweight = log(weight);
18            ldbh = log(DBH);
19         cards;
 
NOTE: The data set WORK.ONE has 47 observations and 9 variables.
NOTE: DATA statement used:
      real time           0.06 seconds
      cpu time            0.06 seconds
19       !        run;
67         ;
68         proc print data=one; TITLE2 'Raw data print'; run;
 
NOTE: There were 47 observations read from the data set WORK.ONE.
NOTE: The PROCEDURE PRINT printed page 1.
NOTE: PROCEDURE PRINT used:
      real time           0.03 seconds
      cpu time            0.03 seconds
 
 
EXST7015: Estimating tree weights from other morphometric variables
Raw data print
 
       Obs                                                Obs
Obs     No     Dbh    Height    Age     Grav    Weight    ID     lweight      ldbh
  1      1     5.7      34       10    0.409      174      a     5.15906    1.74047
  2      2     8.1      68       17    0.501      745      b     6.61338    2.09186
  3      3     8.3      70       17    0.445      814      c     6.70196    2.11626
 
.  . . (see previous handout for full listing)
 
 45     45     8.0      61       13    0.508      614      S     6.41999    2.07944
 46     46     5.2      47       13    0.432      194      T     5.26786    1.64866
 47     47     3.7      33       13    0.389       66      U     4.18965    1.30833
 
70         options ls=99 ps=55; TITLE2 'Scatter plot';
71         proc plot data=one; plot weight*Dbh=obsid;
72         run;
73         options ps=256 ls=132;
74
NOTE: There were 47 observations read from the data set WORK.ONE.
NOTE: The PROCEDURE PLOT printed page 2.
NOTE: PROCEDURE PLOT used:
      real time           0.01 seconds
      cpu time            0.01 seconds

EXST7015: Estimating tree weights from other morphometric variables
Scatter plot
 
                          Plot of Weight*Dbh.  Symbol is value of ObsID.
Weight |
       |
  1800 +
       |
       |                                                                            f     q
       |
  1600 +
       |
       |                                                                             g
       |
  1400 +
       |
       |
       |
  1200 +
       |
       |
       |
  1000 +
       |
       |
       |
   800 +                                                c   z
       |                                              b          t
       |                                           N
       |
   600 +                                             S
       |                                          y
       |                                                  s
       |                                        D
   400 +                                    d
       |                           l    u
       |                      B    COj   o
       |                       F    Pe
   200 +                  A L  mk   J
       |            G           a
       |        Kn Hw h
       |     iI  p    r
     0 +
       |
       -+--------+--------+--------+--------+--------+--------+--------+--------+--------+--------+
        3        4        5        6        7        8        9       10       11       12       13
                                                    Dbh
NOTE: 8 obs hidden.
 
 
75         proc reg data=one lineprinter; ID ObsID;
76            TITLE2 'Simple linear regression';
77            model Weight = Dbh / CLB; output out=next1 p=yhat r=e;
78         run;
NOTE: 47 observations read.
NOTE: 47 observations used in computations.
78       !      options ls=99 ps=55;
79               plot residual.*predicted.=obsid / VREF=0;
80         run;
80       !      options ps=256 ls=132;
81
NOTE: The data set WORK.NEXT1 has 47 observations and 11 variables.
NOTE: The PROCEDURE REG printed pages 3-4.
NOTE: PROCEDURE REG used:
      real time           0.10 seconds
      cpu time            0.10 seconds
 
 

EXST7015: Estimating tree weights from other morphometric variables
Simple linear regression
 
The REG Procedure
Model: MODEL1
Dependent Variable: Weight
 
                             Analysis of Variance
                                    Sum of           Mean
Source                   DF        Squares         Square    F Value    Pr > F
Model                     1        6455980        6455980     433.49    <.0001
Error                    45         670191          14893
Corrected Total          46        7126171
 
Root MSE            122.03740    R-Square     0.9060
Dependent Mean      369.34043    Adj R-Sq     0.9039
Coeff Var            33.04198
 
                                       Parameter Estimates
                     Parameter       Standard
Variable     DF       Estimate          Error    t Value    Pr > |t|       95% Confidence Limits
Intercept     1     -729.39630       55.69366     -13.10      <.0001     -841.56910     -617.22350
Dbh           1      178.56371        8.57640      20.82      <.0001      161.28996      195.83747
 
 
           ---+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
  RESIDUAL |                                                                                      |
           |                                                                                      |
           |                                                                                      |
       400 +                                                                                      +
           |                                                                                      |
           |                                                                        f             |
           |                                                                                      |
           |                                                                                      |
       300 +                                                                                      +
           |                                                                                      |
           |                                                                               q      |
           |                                                                                      |
           |                                                                                      |
       200 +                                                                                      +
           |                                                                                      |
           |  i                                                                                   |
R          |    ?K                                                                    g           |
e          |                                                                                      |
s      100 +      ?                                                                               +
i          |      p  G                                                                            |
d          |        Hw                                   c                                        |
u          |           ?   A   B                    N                                             |
a          |                                           b                                          |
l        0 +           r     ?      l                                                             +
           |                    F                            z                                    |
           |                        C                                                             |
           |                     ?   O                                                            |
           |                     E       u            S                                           |
      -100 +                          j            y                                              +
           |                     a   P       d   D                                                |
           |                         J                                                            |
           |                          e   o                       t                               |
           |                                                                                      |
      -200 +                                                                                      +
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
      -300 +                                               s                                      +
           |                                                                                      |
           |                                                                                      |
           ---+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----
            -100   0   100  200  300  400  500  600  700  800  900 1000 1100 1200 1300 1400 1500
                                     Predicted Value of Weight      PRED
 

82         proc univariate data=next1 normal plot; var e;
83             TITLE3 'Residual analysis'; run;
NOTE: The PROCEDURE UNIVARIATE printed page 5.
NOTE: PROCEDURE UNIVARIATE used:
      real time           0.03 seconds
      cpu time            0.03 seconds
 
 
EXST7015: Estimating tree weights from other morphometric variables
Simple linear regression
Residual analysis
 
The UNIVARIATE Procedure
Variable:  e  (Residual)
 
                            Moments
N                          47    Sum Weights                 47
Mean                        0    Sum Observations             0
Std Deviation      120.703619    Variance            14569.3637
Skewness           0.47869472    Kurtosis            1.04153074
Uncorrected SS     670190.732    Corrected SS        670190.732
Coeff Variation             .    Std Error Mean      17.6064324
 
              Basic Statistical Measures
    Location                    Variability
Mean      0.00000     Std Deviation          120.70362
Median   -0.14041     Variance                   14569
Mode       .          Range                  660.02160
                      Interquartile Range    161.40929
 
 
           Tests for Location: Mu0=0
Test           -Statistic-    -----p Value------
Student's t    t         0    Pr > |t|    1.0000
Sign           M      -0.5    Pr >= |M|   1.0000
Signed Rank    S       -25    Pr >= |S|   0.7946
 
 
                   Tests for Normality
Test                  --Statistic---    -----p Value------
Shapiro-Wilk          W     0.973389    Pr < W      0.3544
Kolmogorov-Smirnov    D     0.084574    Pr > D     >0.1500
Cramer-von Mises      W-Sq  0.044081    Pr > W-Sq  >0.2500
Anderson-Darling      A-Sq  0.354877    Pr > A-Sq  >0.2500
 
Quantiles (Definition 5)
Quantile         Estimate
100% Max       368.769960
99%            368.769960
95%            162.423301
90%            138.710558
75% Q3          75.141444
50% Median      -0.140413
25% Q1         -86.267841
10%           -135.842356
5%            -153.980584
1%            -291.251641
0% Min        -291.251641
 

           Extreme Observations
------Lowest-----        -----Highest-----
   Value      Obs           Value      Obs
-291.252       19         138.711       35
-165.246       20         149.057        7
-153.981       15         162.423        9
-151.699        5         260.775       17
-135.842       36         368.770        6
 
   Stem Leaf                     #  Boxplot                        Normal Probability Plot
      3 7                        1     0         375+                                               *
      3                                             |                                                  +
      2 6                        1     |            |                                           *  ++++
      2                                |            |                                          ++++
      1 56                       2     |            |                                      +++*
      1 00334                    5     |            |                                  +*****
      0 5555666899              10  +-----+         |                              *****
      0 0033                     4  |  +  |         |                         +****
     -0 3210                     4  *-----*         |                     ++***
     -0 997766665                9  +-----+         |                 ******
     -1 4321110                  7     |            |            ******
     -1 755                      3     |            |       * *+*+
     -2                                |            |     ++++
     -2 9                        1     |        -275+ ++*+
        ----+----+----+----+                         +----+----+----+----+----+----+----+----+----+----+
    Multiply Stem.Leaf by 10**+2                         -2        -1         0        +1        +2
 
 
 
 
 
85         proc reg data=one lineprinter; ID ObsID;
86            TITLE2 'Simple linear regression on logarithms';
87            model lWeight = lDbh / CLB; output out=next2 p=yhat r=le;
88         run;
NOTE: 47 observations read.
NOTE: 47 observations used in computations.
88       !      options ls=99 ps=55;
89               plot residual.*predicted.=obsid / VREF=0;
90         run;
90       !      options ps=256 ls=132;
91
NOTE: The data set WORK.NEXT2 has 47 observations and 11 variables.
NOTE: The PROCEDURE REG printed pages 6-7.
NOTE: PROCEDURE REG used:
      real time           0.08 seconds
      cpu time            0.07 seconds
 
 

EXST7015: Estimating tree weights from other morphometric variables
Simple linear regression on logarithms
 
The REG Procedure
Model: MODEL1
Dependent Variable: lweight
 
                             Analysis of Variance
                                    Sum of           Mean
Source                   DF        Squares         Square    F Value    Pr > F
Model                     1       35.94979       35.94979    1236.37    <.0001
Error                    45        1.30846        0.02908
Corrected Total          46       37.25825
 
Root MSE              0.17052    R-Square     0.9649
Dependent Mean        5.49466    Adj R-Sq     0.9641
Coeff Var             3.10337
 
                                       Parameter Estimates
                     Parameter       Standard
Variable     DF       Estimate          Error    t Value    Pr > |t|       95% Confidence Limits
Intercept     1        0.55219        0.14275       3.87      0.0004        0.26469        0.83970
ldbh          1        2.79854        0.07959      35.16      <.0001        2.63824        2.95884
 
 
 
           ------+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+------
  RESIDUAL |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
       0.4 +                                                                                      +
           |                              B                                                       |
           |                                                                                      |
           |                                                                                      |
           |                                    l              N                                  |
           |            K                                         c                               |
       0.2 +                  G       A                          b                                +
           |                                                                                      |
           |                            L       C                                                 |
           |                            T  F                                                      |
           |              Q                      O   u                z             f             |
R          |         I          ?                             y S                                 |
e      0.0 +      i       n                 M            d                                        +
s          |         U        w             ?k    j         D                                     |
i          |                                E                                                     |
d          |              R                                                          g  q         |
u          |                H                    P     o                                          |
a          |                                                             t                        |
l     -0.2 +                                     J                                                +
           |                                      e                                               |
           |                                 a                                                    |
           |                                                                                      |
           |              p                                         s                             |
           |                                                                                      |
      -0.4 +                                                                                      +
           |                                                                                      |
           |                    r                                                                 |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
      -0.6 +                                                                                      +
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           |                                                                                      |
           ------+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+------
               4.00 4.25 4.50 4.75 5.00 5.25 5.50 5.75 6.00 6.25 6.50 6.75 7.00 7.25 7.50 7.75
                                     Predicted Value of lweight     PRED

92         proc univariate data=next2 normal plot; var le;
93             TITLE3 'Residual analysis (log model)'; run;
NOTE: The PROCEDURE UNIVARIATE printed page 8.
NOTE: PROCEDURE UNIVARIATE used:
      real time           0.02 seconds
      cpu time            0.02 seconds
 
 
EXST7015: Estimating tree weights from other morphometric variables
Simple linear regression on logarithms
Residual analysis (log model)
 
The UNIVARIATE Procedure
Variable:  le  (Residual)
 
                            Moments
N                          47    Sum Weights                 47
Mean                        0    Sum Observations             0
Std Deviation      0.16865578    Variance            0.02844477
Skewness           -0.3773174    Kurtosis            0.45701405
Uncorrected SS     1.30845959    Corrected SS        1.30845959
Coeff Variation             .    Std Error Mean      0.02460097
 
              Basic Statistical Measures
    Location                    Variability
Mean     0.000000     Std Deviation            0.16866
Median   0.002340     Variance                 0.02844
Mode      .           Range                    0.82049
                      Interquartile Range      0.20289
 
           Tests for Location: Mu0=0
Test           -Statistic-    -----p Value------
 
Student's t    t         0    Pr > |t|    1.0000
Sign           M       0.5    Pr >= |M|   1.0000
Signed Rank    S        28    Pr >= |S|   0.7705
 
                   Tests for Normality
Test                  --Statistic---    -----p Value------
Shapiro-Wilk          W     0.979294    Pr < W      0.5634
Kolmogorov-Smirnov    D     0.128993    Pr > D      0.0483
Cramer-von Mises      W-Sq  0.069887    Pr > W-Sq  >0.2500
Anderson-Darling      A-Sq  0.396238    Pr > A-Sq  >0.2500
 
Quantiles (Definition 5)
Quantile         Estimate
100% Max       0.36313835
99%            0.36313835
95%            0.26733332
90%            0.22733737
75% Q3         0.10182481
50% Median     0.00234038
25% Q1        -0.10106254
10%           -0.23773581
5%            -0.32982307
1%            -0.45735158
0% Min        -0.45735158
 
 

            Extreme Observations
------Lowest------        ------Highest-----
    Value      Obs            Value      Obs
 
-0.457352       18         0.227337        3
-0.337451       16         0.234177       37
-0.329823       19         0.267333       40
-0.263905        1         0.268304       12
-0.237736        5         0.363138       28
 
 
   Stem Leaf                     #  Boxplot                        Normal Probability Plot
      3 6                        1     |       0.375+                                              +*+
      3                                |            |                                           +++
      2 77                       2     |            |                                        +*+*
      2 1133                     4     |            |                                    ****
      1 9                        1     |            |                                  +*+
      1 0123                     4  +-----+         |                               +***
      0 556668                   6  |     |         |                            +***
      0 013334                   6  *--+--*         |                         ****
     -0 333332210                9  |     |         |                    *****
     -0 8                        1  |     |         |                   *+++
     -1 443000                   6  +-----+         |               ****+
     -1 5                        1     |            |              *++
     -2 40                       2     |            |           +**
     -2 6                        1     |            |        +++*
     -3 43                       2     |            |     ++* *
     -3                                             |  +++
     -4                                             |++
     -4 6                        1     0      -0.475+   *
        ----+----+----+----+                         +----+----+----+----+----+----+----+----+----+----+
    Multiply Stem.Leaf by 10**-1                         -2        -1         0        +1        +2





Modified: August 16, 2004
James P. Geaghan