RESEARCH FOR

Egidijus Kasiulis
Figure 2. Lognormal distribution of average annual wave heights in Klaipėda coast.
which of these distributions provide best fitting, the
BIC and AIC criterion values are calculated and listed
in the same table.
The best fit is obtained for lognormal probability
distribution (Fig. 2). This is indicated by both – BIC
and AIC criteria (-68.65 and -72.07 correspondently).
For calculation of average annual wave heights
in Klaipėda coast depending on probability and
return period, it is preferable to use this distribution
(Table 4).
Wald-Wolfowitz test for maximum annual
wave heights (Fig. 3) shows that observations are
independent (there is no autocorrelation). Similarly as
for average annual wave heights Kendall test shows
existence of a trend. A gradually decreasing curve of
maximum annual wave heights (Fig. 3) follows the
ReseaRch foR RuRal Development 2012
Figure 3. Maximum annual wave heights in Klaipėda coast.
PROBABILITY DISTRIBUTIONS OF WAVE
HEIGHTS IN THE LITHUANIAN COAST
accordingly decreasing curve of average annual wave
heights.
HYFRAN software chi-square test results
indicate that there is no applicable probability
distribution for maximum annual wave heights in
Klaipėda coast; null hypothesis (distribution of the
sample fits the theoretical distribution) is rejected
in all cases. Empirical moments test is applied in
order to confirm these results. This test marks only
one fitting probability distribution for maximum wave
heights – lognormal (Fig. 4). In such case there is no
need to use BIC and AIC criteria test additionally.
For calculating maximum annual wave heights in
Klaipėda coast depending on probability and return
period lognormal probability distribution is used
(Table 4).
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