Holocene history of forest trees on the Bruce Peninsula, southern Ontario

1992 ◽  
Vol 70 (1) ◽  
pp. 6-18 ◽  
Author(s):  
K. D. Bennett
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Deciduous Forest ◽  
Fagus Grandifolia ◽  
Forest History ◽  
Forest Composition ◽  
Southern Ontario ◽  
Historical Factors ◽  
History Of ◽  
Components Analysis

Two new pollen sequences from the Bruce Peninsula, southern Ontario, demonstrate the Holocene history of forests in the area. During the mid- and late Holocene, the southern portion of the peninsula supported a rich deciduous forest, dominated by Acer saccharum and Fagus grandifolia, while the northern portion was dominated by a forest with a much higher proportion of conifers. These two sites are compared numerically with a third site, on Manitoulin Island, by means of principal components analysis. Despite similar bedrock, soils, climate, and topography, the three pollen sequences show a remarkable divergence of Holocene forest history. The role of historical factors in determining forest composition may be much greater than previously appreciated. This study emphasises the need to understand the magnitude of variation between pollen sequences within uniform terrain before ascribing the differences in pollen sequences from contrasting environments (because of climate, soils or topography) to the factors causing the obvious contrast. Key words: Holocene forest history, pollen analysis, principal components analysis, Bruce Peninsula, southern Ontario.

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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