Detail publikace

Evaluation of contamination data with non-detects using censored distributions

FUSEK, M. MICHÁLEK, J. VÁVROVÁ, M.

Originální název

Evaluation of contamination data with non-detects using censored distributions

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

angličtina

Originální abstrakt

When measuring concentration of chemical compounds, we often have to deal with a~situation when the resulting values are found below the limit of detection or limit of quantification of the determination method. In order to statistically evaluate such data, the method of maximum likelihood considering doubly left-censored samples is applied. As a model distribution of measured concentrations, Weibull distribution is considered. Moreover, considering the asymptotic properties of maximum likelihood estimates, concentrations of chemicals can be compared using Wald's test based on the expected Fisher information matrix. Here we show that the described statistical method allows for a better evaluation of the obtained experimental data than commonly used methods where all values below the detection limits are replaced by a~constant. These methods are used for an analysis of the worldwide commonly used synthetic musk compounds (nitro and polycyclic) which were extracted from the fish samples caught upstream (Group 1) and downstream (Group 2) from a high-capacity wastewater treatment plant.

Klíčová slova

Doubly left-censored sample, maximum likelihood, musk compound, Wald's test, Weibull distribution

Autoři

FUSEK, M.; MICHÁLEK, J.; VÁVROVÁ, M.

Rok RIV

2015

Vydáno

3. 12. 2015

ISSN

1018-4619

Periodikum

Fresenius Environmental Bulletin

Ročník

24

Číslo

11c

Stát

Spolková republika Německo

Strany od

4165

Strany do

4172

Strany počet

8

BibTex

@article{BUT115693,
  author="Michal {Fusek} and Jaroslav {Michálek} and Milada {Vávrová}",
  title="Evaluation of contamination data with non-detects using censored distributions",
  journal="Fresenius Environmental Bulletin",
  year="2015",
  volume="24",
  number="11c",
  pages="4165--4172",
  issn="1018-4619"
}