The Exposition of Fuzzy Decision Trees and Their Application in Biology - Advancing Artificial Intelligence Through Biological Process Applications - page 389

Table 8. Information on the initial intervalisation of the BOUT decision attribute

Description (BOUT - hours) Low (L) Medium (M) High (H)

Interval L ≤ 22.403 (43) 22.403 < M ≤ 94.630 (43) 94.630 < H (44)

Mean 13.927 60.840 172.001

Figure 7. Membership functions of the linguistic terms, L, M and H, describing the linguistic variable
version of the BOUT decision attribute

al ., 1990). Hence arousals are assumed either
have direct functional significance, or to permit
important events, such as drinking, feeding,
urinating or sleeping, to occur (Thomas and
Cloutier, 1992; Willis, 1982; Daan et al ., 1991;
Ransome, 1971).
Previous research has suggested that that
euthermic activity after arousal functions to
restore metabolic imbalances developed during
the previous torpor bout. If this is correct, torpor
bout duration should decrease with increasing
temperature, as metabolic processes are faster
at higher temperatures, and a critical metabolic
imbalance will be reached faster (see for example,
Twente and Twente, 1965). Models assuming that
evaporative water loss determines torpor bout
duration make similar predictions (Thomas and
Geiser, 1997).
The data considered here was made up of a
sample of 130 continually monitored topor bouts
- BOUT (measured in hours), undertaken by the
bats, with a range of BOUT that goes from 1.67
hours to 257.27 hours. As in the previous FDT
analysis, three intervals are identified to offer an

initial partitioning of the BOUT decision attribute,
which are later associated with the linguistic
terms, low (L), medium (M) and high (H). An
equal frequency based intervalisation of the
BOUT values was employed, see Table 8.
In Table 8, the intervals shown define the
majority support sub-domains of the BOUT lin-
guistic terms, L, M and H, where the values in
brackets are the numbers of bouts included in each
interval. Also shown are the means of the BOUT
values included in each interval. The interval
details shown in Table 8 are used to construct
the respective MF for each of the linguistic terms
L, M and H, so used as the necessary defining
values [α j, 1 , α j, 2 , α j, 3 , α j, 4 , α j, 5 ] for each term, previ-
ously defined.
To demonstrate the assignment of values to the
defining values, with the linguistic term BOUT =
M (2 nd interval) its mean value is 60.840, hence α 2,3
= 60.840. The neighbouring defining values, α j, 2
and α j, 4 , around α j, 3 are the left and right bound-
ary values of that interval, respectively (so here
they are α 2,2 = 22.40 and α 2,4 = 94.63). The final
outer defining values, α j, 1 and α j, 5 , are the middle