HIERARCHAL INDUCTIVE PROCESS MODELING AND ANALYSIS ...

eally well (Atanasova et al. 2007). While this framework can evaluate only able one
state variable at the time, HIPM is capable of evaluating multiple variables simultaneously
; however we are faced with an under-constrained optimization problem
since we want to select models with data for only a couple of the variables. Using
CIAO simulated data we were able to explore and investigate the response of HIPM
for the phytoplankton dynamic in the Ross Sea. Even though we did not use real-life
data the results generate conclusions. First, more data is not synonymous with fewer
models being selected. This conclusion must be tested to see if it can be generalized
to other ecosystems or if becomes obsolete with a refined and improved processlibrary.
Secondly, the result that zooplankton contains more restrictive power than
the other state variables was attained only through multiple experiments using a
full data set. There is room for further work in the area of exploratory statistics
with the median activation value in order to develop a formal procedure that would
assist scientist in their decision making process for data collection.
The number of processes taken into consideration for the Ross Sea ecosystem
make for an extensive process-library, which creates models with very intricate and
complex structures. A direction for improvement would be to look at some sort of
measure of complexity for the models, somewhat motivated by the law of parsimony
that states that the simplest explanation is often the best.This could be coupled
with a measure of distance between models; this two concepts could potentially be
of great value when comparing different models. However, at this point the more
plausible and logical step for future research would be first to incorporate diatoms
in the way in which phytoplankton is defined in the process library and second to
switch from a mean square error to a maximum square error, which in my opinion
would yield very different results. In the long run, this thesis could be the premise
to a protocol towards decision making in the data collection process.
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