Selected

There´s a large variety of statistical methods existing. Only a certain part of them is required for evaluation of biotests. Let ToxRat  take care for the selection! Statistical methods being relevant in ecotoxicology are waiting for you.

Effective.

Simple statistics:

  • mean, median, standard deviation, confidence interval, minimum and maximum

Statistical testing

  • Variance analysis (ANOVA, Kruskal-Wallis Test, chi²- and exact contingency table tests)
  • Pretests on normal distribution  (R/S-Test, Kolmogorrov-Smirnov Test, Shapiro Wilks Test)
  • Pre-tests on homogenity of variance (Cochran, Bartlett, Levene)
  • Pairwise comparisons (Student-t-Test, Welch-t-Test, Mann-Whitney-U-Test, Fisher Exact Binomial Test)
  • Multiple Comparisons (t-Test with Bonferroni-Correction, Dunnett Test, Williams Test, Welch-t-Test with Bonferroni-Correction, Wilcoxon-Mann-Withney-U-Test with Bonferroni-Correction, Chi² - and Fisher Exact Test with Bonferroni Correction)
  • Tests for outliers (Dixon/Grubbs; Hampel)

Dose-Response-Curves :
up to 6 user definable effect levels, 95% and 99% Confidence limits

  • Models: Probit, Logit, Weibull, logistic function with 4 parameters
  • Fitting: linear / linear weighted / linear max. likelihood
  • Parallel Line Assay and Potency Estimation
  • Abbott Correction

Alternative methods to determine the EC50:
Moving Averages, Simple Interpolation, Trimmed Spearman Kaerber

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