Ewa Skrzypczak-Pietraszek
Czasopismo Techniczne, Mechanika Zeszyt 4-M 2016, 2016, s. 95 - 100
https://doi.org/10.4467/2353737XCT.16.238.5987Shainin’s approach is a specific sequential heuristic aimed at finding and ranking the most important factors which impact the investigated process. The sequential aspect of the approach is simultaneously its strongest and weakest side, because just after detection of the most important factor, the further analysis is stopped without any additional cost. However, such a detection may take place at the end of the whole sequence. This paper tries to answer the question if the dominant factor may be hidden by interactions with other factors.
Ewa Skrzypczak-Pietraszek
Czasopismo Techniczne, Mechanika Zeszyt 4-M 2016, 2016, s. 119 - 125
https://doi.org/10.4467/2353737XCT.16.242.5991The well-known statistical tests have been developed on the basis of many additional assumptions, among which the normality of a data source distribution is one of the most important. The outcome of a test is a p-value which may is interpreted as an estimation of a risk for a false negative decision i.e. it is an answer to the question “how much do I risk if I deny?”. This risk estimation is a base for a decision (after comparing with a significance level α): reject or not. This sharp trigger – p-level greater than α or not – ignores the fact that a context is rather smooth and evolves from “may be” through “rather not” to “certainly not”. An alternative option for such assessments is proposed by a fuzzy statistics, particularly by Buckley’s approach. The fuzzy approach introduces a better scale for expressing decision uncertainty. This paper compares three approaches: a classic one based on a normality assumption, Buckley’s theoretical one and a bootstrap-based one