The Use of Principal Components Analysis Techniques on Nimbus-7 Coastal Zone Color Scanner Data to Define Mesoscale Ocean Features through a Warm Humid Atmosphere

1984 ◽  
Author(s):  
R. J. Holyer ◽  
P. E. La Violette
Keyword(s):  
Principal Components Analysis ◽  
Coastal Zone ◽  
Principal Components ◽  
Scanner Data ◽  
Humid Atmosphere ◽  
Analysis Techniques ◽  
Components Analysis ◽  
Color Scanner

Morphological variation in relation to the taxonomy of the destructor group of the genus Cherax

1988 ◽  
Vol 2 (1) ◽  
pp. 55 ◽  
Author(s):  
A Sokol
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Morphological Variation ◽  
Analysis Of Covariance ◽  
Bivariate Analysis ◽  
Morphological Divergence ◽  
Analysis Techniques ◽  
Late Tertiary ◽  
Outgroup Species ◽  
Components Analysis

The present study was directed at clarifying the taxonomy of the destructor group of the genus Cherax. This group was defined by Riek (1969) to include four species: C. destructor Clark, C. albidus Clark, C. davisi Clark and C. esculus Riek. Approximately 1600 specimens representing over 80 localities were examined, including specimens from three outgroup species; C. rotundus, C. punctatus and C. dispar. Variation in 16 metric and 30 multistate characters was analysed by bivariate (analysis of covariance) and multivariate (principal components analysis) techniques. None of the taxonomic analyses supported the distinction of C. davisi or C. esculus from C. destructor, which suggests that the two former species be synonymised with the last. By contrast, C. albidus was found to be morphologically distinct. The pattern and timing of speciation of C. albidus and C. destructor are unclear but may relate to the increase in aridity in inland Australia during the late Tertiary. The analyses also indicated that heterochrony may underly the morphological divergence of these two species.

Diagnoses Generated by Numerical Taxonomic Methods Applied to Standard Blood Variables

1980 ◽  
Vol 19 (04) ◽  
pp. 205-209
Author(s):  
L. A. Abbott ◽  
J. B. Mitton
Keyword(s):  
Liver Cirrhosis ◽  
Renal Disease ◽  
Principal Components Analysis ◽  
Discriminant Function ◽  
Principal Components ◽  
Discriminant Function Analysis ◽  
Chronic Renal Disease ◽  
Function Analysis ◽  
Infectious Hepatitis ◽  
Components Analysis

Data taken from the blood of 262 patients diagnosed for malabsorption, elective cholecystectomy, acute cholecystitis, infectious hepatitis, liver cirrhosis, or chronic renal disease were analyzed with three numerical taxonomy (NT) methods : cluster analysis, principal components analysis, and discriminant function analysis. Principal components analysis revealed discrete clusters of patients suffering from chronic renal disease, liver cirrhosis, and infectious hepatitis, which could be displayed by NT clustering as well as by plotting, but other disease groups were poorly defined. Sharper resolution of the same disease groups was attained by discriminant function analysis.

Assamese vowels and vowel harmony

2020 ◽  
Vol 6 (2) ◽  
pp. 151-183
Author(s):  
Diana B. Archangeli ◽  
Jonathan Yip
Keyword(s):  
Physical Properties ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Vowel Harmony ◽  
Language Community ◽  
Acoustic Data ◽  
Apparent Loss ◽  
Root Position ◽  
Components Analysis ◽  
Open Question

AbstractBased on impressionistic and acoustic data, Assamese is described as having a phonological tongue root harmony system, with blocking by certain phonological configurations and over-application in certain morphological contexts. This study explores physical properties of the patterns using ultrasonic imaging to determine whether the impressionistic descriptions match what speakers actually do. Principal components analysis (PCA) determines that most participants produce a contrast in tongue root position in the appropriate contexts, though there is less of an impact on tongue root with greater distance from the triggering vowel. Analysis uses the root mean squared distance (RMSD) calculation to determine whether both blocking and over-application take effect. The blocking results conform to the impressionistic descriptions. With over-application, [e] and [o] are expected; while some speakers clearly produce these vowels, others articulate a vowel that is indeterminant between the expected [e]/[o] and an unexpected [ɛ]/[ɔ]. No speaker consistently showed the expected tongue root position in all contexts, and some speakers appeared to have lost the contrast entirely, yet all are considered to be speakers of the same dialect of Assamese. Whether this (apparent) loss is a consequence of crude research methodologies or accurately reflects what is happening within the language community remains an open question.

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