Matches in SemOpenAlex for { <https://semopenalex.org/work/W2980565598> ?p ?o ?g. }
- W2980565598 endingPage "316" @default.
- W2980565598 startingPage "303" @default.
- W2980565598 abstract "Using sampling experiments, we found that, when there are fewer groups than variables, between-groups PCA (bgPCA) may suggest surprisingly distinct differences among groups for data in which none exist. While apparently not noticed before, the reasons for this problem are easy to understand. A bgPCA captures the g − 1 dimensions of variation among the g group means, but only a fraction of the $$sum {n_{i} } - g$$ dimensions of within-group variation ( $$n_{i}$$ are the sample sizes), when the number of variables, p, is greater than g − 1. This introduces a distortion in the appearance of the bgPCA plots because the within-group variation will be underrepresented, unless the variables are sufficiently correlated so that the total variation can be accounted for with just g − 1 dimensions. The effect is most obvious when sample sizes are small relative to the number of variables, because smaller samples spread out less, but the distortion is present even for large samples. Strong covariance among variables largely reduces the magnitude of the problem, because it effectively reduces the dimensionality of the data and thus enables a larger proportion of the within-group variation to be accounted for within the g − 1-dimensional space of a bgPCA. The distortion will still be relevant though its strength will vary from case to case depending on the structure of the data (p, g, covariances etc.). These are important problems for a method mainly designed for the analysis of variation among groups when there are very large numbers of variables and relatively small samples. In such cases, users are likely to conclude that the groups they are comparing are much more distinct than they really are. Having many variables but just small sample sizes is a common problem in fields ranging from morphometrics (as in our examples) to molecular analyses." @default.
- W2980565598 created "2019-10-25" @default.
- W2980565598 creator A5033318405 @default.
- W2980565598 creator A5062254329 @default.
- W2980565598 creator A5071901201 @default.
- W2980565598 date "2019-10-18" @default.
- W2980565598 modified "2023-10-10" @default.
- W2980565598 title "Seeing Distinct Groups Where There are None: Spurious Patterns from Between-Group PCA" @default.
- W2980565598 cites W1490832211 @default.
- W2980565598 cites W1527466317 @default.
- W2980565598 cites W1539401426 @default.
- W2980565598 cites W1593702583 @default.
- W2980565598 cites W1772895764 @default.
- W2980565598 cites W1821979374 @default.
- W2980565598 cites W1850430998 @default.
- W2980565598 cites W1908011449 @default.
- W2980565598 cites W1932063339 @default.
- W2980565598 cites W1964791943 @default.
- W2980565598 cites W1994100095 @default.
- W2980565598 cites W2001619934 @default.
- W2980565598 cites W2012971267 @default.
- W2980565598 cites W2014154358 @default.
- W2980565598 cites W2037357509 @default.
- W2980565598 cites W2039873798 @default.
- W2980565598 cites W2059249244 @default.
- W2980565598 cites W2059615944 @default.
- W2980565598 cites W2067150228 @default.
- W2980565598 cites W2067315043 @default.
- W2980565598 cites W2071703572 @default.
- W2980565598 cites W2074557013 @default.
- W2980565598 cites W2080703293 @default.
- W2980565598 cites W2116967918 @default.
- W2980565598 cites W2121096133 @default.
- W2980565598 cites W2124024366 @default.
- W2980565598 cites W2126187362 @default.
- W2980565598 cites W2131666115 @default.
- W2980565598 cites W2132225134 @default.
- W2980565598 cites W2133385271 @default.
- W2980565598 cites W2134966509 @default.
- W2980565598 cites W2139101237 @default.
- W2980565598 cites W2141612033 @default.
- W2980565598 cites W2154635002 @default.
- W2980565598 cites W2159176912 @default.
- W2980565598 cites W2161597133 @default.
- W2980565598 cites W2169380360 @default.
- W2980565598 cites W2169973887 @default.
- W2980565598 cites W2225936424 @default.
- W2980565598 cites W2401143106 @default.
- W2980565598 cites W2405411212 @default.
- W2980565598 cites W2465241759 @default.
- W2980565598 cites W2533759227 @default.
- W2980565598 cites W2539308372 @default.
- W2980565598 cites W2569402445 @default.
- W2980565598 cites W2597672661 @default.
- W2980565598 cites W2604243177 @default.
- W2980565598 cites W2623319323 @default.
- W2980565598 cites W2730822049 @default.
- W2980565598 cites W2740754384 @default.
- W2980565598 cites W2741716125 @default.
- W2980565598 cites W2768725243 @default.
- W2980565598 cites W2768812036 @default.
- W2980565598 cites W2787148882 @default.
- W2980565598 cites W2801928643 @default.
- W2980565598 cites W2805964580 @default.
- W2980565598 cites W2921445455 @default.
- W2980565598 cites W2944744814 @default.
- W2980565598 cites W2950283901 @default.
- W2980565598 cites W32195621 @default.
- W2980565598 cites W4211153193 @default.
- W2980565598 cites W4256209565 @default.
- W2980565598 cites W587897240 @default.
- W2980565598 cites W653575891 @default.
- W2980565598 doi "https://doi.org/10.1007/s11692-019-09487-5" @default.
- W2980565598 hasPublicationYear "2019" @default.
- W2980565598 type Work @default.
- W2980565598 sameAs 2980565598 @default.
- W2980565598 citedByCount "67" @default.
- W2980565598 countsByYear W29805655982020 @default.
- W2980565598 countsByYear W29805655982021 @default.
- W2980565598 countsByYear W29805655982022 @default.
- W2980565598 countsByYear W29805655982023 @default.
- W2980565598 crossrefType "journal-article" @default.
- W2980565598 hasAuthorship W2980565598A5033318405 @default.
- W2980565598 hasAuthorship W2980565598A5062254329 @default.
- W2980565598 hasAuthorship W2980565598A5071901201 @default.
- W2980565598 hasBestOaLocation W29805655982 @default.
- W2980565598 hasConcept C105795698 @default.
- W2980565598 hasConcept C111030470 @default.
- W2980565598 hasConcept C114614502 @default.
- W2980565598 hasConcept C121332964 @default.
- W2980565598 hasConcept C126780896 @default.
- W2980565598 hasConcept C129848803 @default.
- W2980565598 hasConcept C149782125 @default.
- W2980565598 hasConcept C178650346 @default.
- W2980565598 hasConcept C194257627 @default.
- W2980565598 hasConcept C198531522 @default.
- W2980565598 hasConcept C27438332 @default.
- W2980565598 hasConcept C2778334786 @default.