The multivariate analyses were run on either R or SAS. The appendix link at the end of each section links to the appropriate appendix where the code and output for each analysis can be viewed. The images link to the specified figures.

Both the PCA and the CLUSTER analysis show that there is a definite separation between the known early successional species and known mid and late successional species, but the separation between known late and mid successional species is less defined. A separation between each of the succession classification would have been ideal, but these results do provide some information for the second objective of this project. Profitable mid and late successional species who act like early successional species,can be planted in clear cut stands which could improve the success rate of replanted clear cut stands in the Philippines.

FIGUREs 10 & 11 are the
outputs for the princomp PCA analysis. Red, blue and green indicate known early, mid and late successional species
respectively. Uncolored values represent species whose successional classification is unknown. FIGURE 10 shows that the
early successional species group together based on the clustering values in both the Young Growth stand (PLOTA) and
the Old Growth stand (PLOTC) and the slope of the dbh distribution in the Young Growth stand (PLOTA). Species 30
(TABUYOG *(Ficus congesta Roxb.)* from the Moraceae family) is the only exception to the grouping. Tabuyog has
almost a 50% higher frequency then the species with the second highest frequency in the Young Growth stand (PLOTA).
This drastic difference can possibly explain the grouping discrepancy. FIGURE 11 shows the same PCA analysis as in
FIGURE 10, but values are plotted based on the clustering values in the Young Growth stand (PLOTA) and the slope of
the dbh distribution in the Old Growth stand (PLOTC). By changing the values that are plotted in the PCA biplot the
direction of the frequency and slope of the dbh distribution in the Young Growth stand vectors overlay one another
and as a result pulls Tabuyog into the early successional grouping. The PCA scores can be viewed in the
PCA Data Table.

The CLUSTER analysis gave a similar result as the PCA analysis. FIGURE 12 is the resulting dendrogram showing the distances between the species based on the given variables. The same colour legend was applied to the dendrogram as the PCA analysis. As in the PCA, there is a clear separation between the known early succession species and the mid and late successional species, but the separation between the known mid and late successional species is less defined.

Based on the result of the PCA and CLUSTER analysis further multivariate analyses can be done to predict the succession classification for the unknown species and to determine which variable have the greatest impact on the classification.

FIGURE 10FIGURE 11

FIGURE 12

PCA Appendix (Appendix B)

CLUSTER Appendix (Appendix C)

The DISCRIM Appendix link shows the F-statistics for the squared distances among the group centroids for each successional classifications. The resulting degree of freedom in the numerator is NDF=4 and the degrees of freedom in the denominator is DDF=8. Based on the degrees of freedom and the adjusted T^2-value the critical F-value for the F-test is approximately 0.17. Test values from the PROC DISCRIM analysis were all larger then the critical F-value and the null hypothesis can be rejected in each case. This result is encouraging since it shows that there is a definite separation amongst the early, mid and late successional species based on the variables that were analyzed.

DISCRIM Appendix (Appendix D)
PROC DISCRIM automatically classified the succession classifications while calculating the F-statistics. Based on
the known 5 early, 4 mid and 5 late successional species a model was generated to classify the remaining 21 unknown
species.
The succession classification with the highest probability determined the species classification. The results of the
predicted classifications were 13 early, 14 mid and 8 late successional species. Incorrect classification probabilities
from PROC DISCRIM were calculated as follows:

Classification Early> Mid Late Overall
Error Probability 0.0 0.25 0.2 0.15

The probability for incorrectly classifying a mid or late succesional species as an early successional species is high, but
can be explained by the low frequency of test points. While only 1 mid and 1 late successional species was incorrectly
classified, only 4 mid and 5 late successional species were known, therefore even incorrectly classifying 1 species results
in large error probabilities. To obtain more realistic error probabilities more known species would have to be tested using
this discriminate analysis classification.

Select the link to view the Predicted DataTable which shows the predicted succession classification and the predictor percentages for each classification.

PROC CANDISK rotates the values of the variable until a clear distinction between the successional classifications is made. FIGURE 13 is the resulting graph that illustrates the grouping of each of the successional classifications.

FIGURE 13DISCRIM Appendix (Appendix D)

CANDISK Appendix (Appendix E)

The STEPDISK function used F-values based on an analysis of covariances to establish which variables have the greatest significance in determining the succession classification for species. The stepwise selection procedure suggested that the frequency in the Old Growth stand (PLOTC) and the slope of the dbh distribution in the Young Growth stand (PLOTA) contribute significantly in classifying whether a species is an early, mid or late successional species. The frequency in the Young Growth stand (PLOTA) and the Mid Growth stand (PLOTB), clustering in all stand, and the slope of the dbh distribution in the Mid Growth stand (PLOTB) and the Old Growth stand (PLOTC) should therefore be dropped in future analysis. This suggests that further tests need to be done on frequency, clustering, and the dbh distribution within the stands to verify this result, since known traits of early, mid and late successional species are not suggested as significant.

STEPDISK Appendix (Appendix F)
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INTRODUCTION

DATA DETAILS

MULTIVARIATE METHODS

MULTIVARIATE RESULTS & DISCUSSION

CONCLUSION

APPENDICES

REFERENCES & ACKNOWLEDGEMENTS

DATA PREPARATION METHODS

DATA PREPARATION RESULTS & DISCUSSION

PRELIMINARY ANALYSIS