This module will be used where data distribution may not be normal, when normality is in doubt, or when type of distribution is known apriori, but the parameters of the distribution are needed. This module is essential when risk of exceeding a given value is to be assessed.
Probability models - Pdf manual
Example:
Hg concentration in soil samples
Task: Find the true value and a 99% quantile of the distribution. What is the risk of exceeding the limit concentration of 8mg/kg?
Data:
ID |
Hg_Concentration |
TE_R-006 |
1.1.1966 |
TE_R-617 |
1.1.1956 |
TE_R-512 |
1.1.1966 |
TE_R-807 |
1.1.1952 |
TE_R-271 |
1.1.1956 |
TE_R-624 |
1.1.1956 |
TE_R-908 |
1.1.1933 |
TE_R-911 |
1.1.1947 |
TE_R-945 |
1.1.1961 |
TE_R-753 |
1.1.1966 |
TE_R-449 |
1.1.1966 |
TE_R-692 |
1.1.1970 |
TE_R-272 |
1.1.1966 |
TE_R-781 |
1.1.1980 |
TE_R-823 |
1.1.1966 |
TE_R-117 |
1.1.1961 |
TE_R-968 |
1.1.1989 |
TE_R-389 |
2.8.2009 |
Dialog window:
Protocol:
Probabilistic models |
Maximum likelihood method (MLE) |
|
Task name : |
Sheet1 |
Data: |
All |
|
List of analyzed distributions |
Symetric models |
Parameters |
|
|
|
Distribution |
Likelihood |
P-P correlation |
A |
B |
|
|
Normal |
-181,6785248 |
0,9093237246 |
23673,33333 |
6015,475161 |
|
|
Cauchy |
-180,2259792 |
0,9442434739 |
23673,33205 |
2058,729961 |
|
|
Logisitic |
-180,7001734 |
0,9283511579 |
23673,33324 |
2987,734462 |
|
|
Laplace |
-179,1624181 |
0,9243167929 |
24107,99995 |
3867,519046 |
|
|
Uniform |
-184,3012672 |
0,7858115537 |
12055 |
40027 |
|
|
|
Asymetric models |
Parameters |
|
|
|
Distribution |
Likelihood |
P-P correlation |
A |
B |
C |
|
Gamma |
-183,4977216 |
0,8804793092 |
9257,800497 |
5645,342342 |
2,802049929 |
|
Gumbel |
-181,3723066 |
0,9240551682 |
20873,80725 |
5090,558443 |
|
|
Triangular |
-181,7168227 |
0,880124682 |
9807,619917 |
41968,85541 |
23511,5318 |
|
Exoponential |
-186,4862994 |
0,7621335177 |
12054,87945 |
11618,45345 |
|
|
Weibull |
-182,1741659 |
0,8941368252 |
3123,866839 |
22986,89688 |
3,594183413 |
|
Lognormal |
-180,950687 |
0,926506368 |
-10233,34365 |
10,41711622 |
0,1680905563 |
|
|
Sample moments |
Mean |
Variance |
Skewness |
Kurtosis |
Median |
|
|
23673,33333 |
36185941,41 |
0,9698171422 |
5,284355292 |
24108 |
|
|
|
Model moments |
Distribution |
Mean value |
Variance |
Skewness |
Kurtosis |
Median |
Modus |
Normal |
23673,33333 |
36185941,41 |
0 |
3 |
23673,33333 |
23673,33333 |
Cauchy |
not def. |
not def. |
not def. |
not def. |
23673,33205 |
23673,33205 |
Logisitic |
23673,33324 |
29367196,12 |
0 |
4,2 |
23673,33324 |
23673,33324 |
Laplace |
24107,99995 |
29915407,14 |
0 |
6 |
24107,99995 |
24107,99995 |
Uniform |
26041 |
65202732 |
0 |
1,8 |
26041 |
not def. |
Gamma |
25076,33161 |
89301023,48 |
1,194791325 |
2,141289467 |
- |
19430,98927 |
Gumbel |
23812,1573 |
42626468,18 |
1,1395 |
5,4 |
22739,56269 |
20873,80725 |
Triangular |
25096,00238 |
43411529,56 |
0,1428981506 |
2,4 |
24740,82112 |
23511,5318 |
Exoponential |
23673,3329 |
134988460,6 |
2 |
9 |
20108,1777 |
12054,87945 |
Weibull |
23835,67984 |
40954627,69 |
0,001959281692 |
2,716462326 |
24968,10965 |
25091,4316 |
Lognormal |
23669,13593 |
32938162,92 |
- |
- |
23193,55545 |
22262,31508 |
|
Quantiles and probability |
Distribution |
Probab(x=8) |
Quant(0,01) |
Quant(0,99) |
|
|
|
Normal |
4,175876848E-005 |
9679,247478 |
37667,41919 |
|
|
|
Logisitic |
0,0003629694598 |
9944,338116 |
37402,33085 |
|
|
|
Cauchy |
0,02762135151 |
-41836,51353 |
89183,17716 |
|
|
|
Laplace |
0,0009833631026 |
8978,180302 |
39237,82262 |
|
|
|
Uniform |
0 |
12334,72 |
39747,28 |
|
|
|
Gamma |
0 |
11346,09658 |
54687,48048 |
|
|
|
Gumbel |
6,648953412E-027 |
13099,61245 |
44291,1337 |
|
|
|
Triangular |
0 |
11906,98456 |
39532,43967 |
|
|
|
Exoponential |
0 |
12171,64959 |
65559,83166 |
|
|
|
Weibull |
0 |
9515,806658 |
38280,99613 |
|
|
|
Lognormal |
9,789946631E-013 |
12375,1088 |
39188,77047 |
|
|
|
Graphical output:
|