scholarly journals IV. Contributions to the mathematical theory of evolution. III. Regression, heredity, and panmixia

1896 ◽  
Vol 59 (353-358) ◽  
pp. 69-71 ◽  
Keyword(s):  
Mathematical Theory ◽  
Quantitative Measurement ◽  
Correlation Coefficients ◽  
Regression Coefficients ◽  
Wide Field ◽  
Theory Of Evolution ◽  
Standard Deviations ◽  
Physiological Theory

The object of this paper is to develop the methods and generalise the conclusions of Mr. Francis Gallon’s work on ‘Natural Inheritance.’ It endeavours to show the wide field which a purely statistical (as distinguished from a mechanical or physiological) theory of heredity may be made to cover. In order to do this it is needful to define certain biological terms in such a manner that they are capable of quantitative measurement, the symbols in terms of which they are expressed being the standard-deviations, correlation-coefficients, and regression-coefficients already well known from the labours of Mr. Galton.

Relationship between Coffee Prices in Spot and Futures Markets-An Empirical Analysis

2020 ◽  
pp. 180-188
Keyword(s):  
New York ◽  
Correlation Coefficients ◽  
Strong Relationship ◽  
Futures Market ◽  
Regression Coefficients ◽  
Futures Prices ◽  
Market Prices ◽  
Spot Prices ◽  
Correlation And Regression Analysis ◽  
Highly Correlated

The present study explored the relationship between spot and futures coffee prices. The Correlation and Regression analysis were carried out based on monthly observations of International Coffee Organization (ICO) indicator prices of the four groups (Colombian Milds, Other Milds, Brazilian Naturals, and Robustas) representing Spot markets and the averages of 2nd and 3rd positions of the Intercontinental Exchange (ICE) New York for Arabica and ICE Europe for Robusta representing the Futures market for the period 1990 to 2019. The study also used the monthly average prices paid to coffee growers in India from 1990 to 2019. The estimated correlation coefficients indicated both the Futures prices and Spot prices of coffee are highly correlated. Further, estimated regression coefficients revealed a very strong relationship between Futures prices and Spot prices for all four ICO group indicator prices. Hence, the ICE New York (Arabica) and ICE Europe (Robusta) coffee futures prices are very closely related to Spot prices. The estimated regression coefficients between Futures prices and the price paid to coffee growers in India confirmed the positive relationship, but the dispersion of more prices over the trend line indicates a lesser degree of correlation between the price paid to growers at India and Futures market prices during the study period.

scholarly journals II.—A mathematical theory of evolution, based on the conclusions of Dr. J. C. Willis, F. R. S

1925 ◽  
Vol 213 (402-410) ◽  
pp. 21-87 ◽  
Keyword(s):  
Mathematical Theory ◽  
Small Areas ◽  
Theory Of Evolution ◽  
Precise Formulation ◽  
Statistical Studies

The following work is founded on that conception of evolution, the most recent and precise formulation of which is due to Dr. J. C. Willis, and represents an attempt to develop the quantitative consequences of the conception. By his statistical studies of distribution Dr. Willis was led to two conclusions:— (1) Species occupying large areas are, on the whole , older than those occupying small areas, provided that allied forms are compared.

scholarly journals Variation of grain growth of wheat cultivars

1970 ◽  
Vol 34 (3) ◽  
pp. 351-359
Author(s):  
SK Adhikary ◽  
MZ Alam ◽  
NK Paul
Keyword(s):  
Triticum Aestivum ◽  
Linear Regression ◽  
Grain Growth ◽  
Growth Pattern ◽  
Correlation Coefficients ◽  
Triticum Aestivum L ◽  
Grain Weight ◽  
Regression Coefficients ◽  
Cultivar Differences ◽  
Wheat Cultivars

An experiment was carried out to study the grain growth pattern of wheat (Triticum aestivum L.) cultivars and to find out association and linear regression of spike weight and grain weight with time. Spike characters indicated that cultivar differences were significant in all the cases with a few exceptions. Linear regression and correlation coefficients revealed that the association between both spike weight and grain weight with time were highly positively significant among the cultivars but their regression coefficients were non- significant. Key Words: Grain growth, correlation, regression, wheat. DOI: 10.3329/bjar.v34i3.3960 Bangladesh J. Agril. Res. 34(3) : 351-359, September 2009

Papers read to the Society, November 16, 1899

1900 ◽  
Vol 65 (413-422) ◽  
pp. 433-433
Keyword(s):  
Experimental Research ◽  
Electrical Resistance ◽  
Electromotive Force ◽  
Quantitative Measurement ◽  
Potential Difference ◽  
Pelvic Plexus ◽  
Especial Reference ◽  
Theory Of Evolution ◽  
Earthquake Motion

I. “Note on the Electromotive Force of the Organ Shock, and on the Electrical Resistance of the Organ, in <italic>Malapterurus electricus</italic>” By Professor F. Gotch, F. R. S., and G. J. Burch. II. "On the Formation of the Pelvic Plexus, with especial Reference to the Nervus Collector, in the Genus <italic>Mustelus</italic>." By R. O. Punnett. Communicated by Dr. Gadow, F. R. S. III. “On the Least Potential Difference required to produce Discharge through various Gases.” By the Hon. R. J. Strutt. Communicated by Lord Rayleigh, F. R. S. IV. “Mathematical Contributions to the Theory of Evolution. VII — On certain Formulae in the Theory of Correlation, and their Application to the Inheritance of Characters not capable ot Quantitative Measurement.” By Professor Karl Pearson, F. R. S. V. “On the Propagation of Earthquake Motion to Great Distances" By R. D. Oldham. Communicated by Sir R. S. Ball, F. R. S. VI. “An Experimental Research on some Standards of Light. By J. E. Petavel. Communicated by Lord Rayleigh, F. R. S.

Experimental Study on Behavior of Bubbles and Temperature Fluctuation of Heat Transfer Surface by Using Heat Transfer Surface With Artificial Cavities Created by MEMS Technology

2009 ◽  
Author(s):  
Takato Sato ◽  
Yasuo Koizumi ◽  
Hiroyasu Ohtake
Keyword(s):  
Heat Transfer ◽  
Surface Temperature ◽  
Correlation Coefficients ◽  
Side Surface ◽  
Nucleate Boiling ◽  
Heat Transfer Surface ◽  
Back Side ◽  
Mems Technology ◽  
Standard Deviations ◽  
Thermal Influence

Pool nucleate boiling heat transfer experiments were performed for water using heat transfer surfaces having a unified cavity. A single cylindrical hole of 10 μm in diameter and 40 μm in depth was formed on a mirror-finished silicon wafer of 0.2 mm in thickness using the Micro-Electro Mechanical Systems (MEMS) technology. This silicon plate was used as the heat transfer surface. The back side of the heat transfer surface was heated by a semi-conductor laser beam. The back-side surface temperature was measured by a radiation thermograph with a temperature resolution of 0.08 K and a time resolution of 3 ms/line. Experiments were conducted in the range up to 1.35 × 105 W/m2. The standard deviations of the local fluctuating heat transfer surface temperature were calculated. So the cross-correlation coefficients between the cavity center and a certain point were calculated by using the standard deviations and the time-series surface temperature data. Then, the intensity of the thermal influence exerted by the boiling bubbles on the local position was derived. The thermal influence extents determined from the intensity were 2.1 – 3.3 times larger than the mean diameter of all departure bubbles in the present experimental range.

scholarly journals Development and Validation of Spectrophotometric Methods for Determination of Fluoxetine, Sertraline, and Paroxetine in Pharmaceutical Dosage Forms

2005 ◽  
Vol 88 (1) ◽  
pp. 38-45 ◽  
Author(s):  
Ibrahim A Darwish
Keyword(s):  
Correlation Coefficients ◽  
Dosage Forms ◽  
Pharmaceutical Dosage Forms ◽  
Factors Affecting ◽  
Spectrophotometric Methods ◽  
Linear Relationships ◽  
Relative Standard ◽  
Optimum Reaction ◽  
Standard Deviations

Abstract Three simple and sensitive spectrophotometric methods were developed and validated for determination of the hydrochloride salts of fluoxetine, sertraline, and paroxetine in their pharmaceutical dosage forms. These methods were based on the reaction of the N-alkylvinylamine formed from the interaction of the free secondary amino group in the investigated drugs and acetaldehyde with each of 3 haloquinones, i.e., chloranil, bromanil, and 2,3-dichloronaphthoquinone, to give colored vinylamino-substituted quinones. The colored products obtained with chloranil, bromanil, and 2,3-dichloronaphthoquinone exhibit absorption maxima at 665, 655, and 580 nm, respectively. The factors affecting the reactions were studied and optimized. Under the optimum reaction conditions, linear relationships with good correlation coefficients (0.9986–0.9999) were found between the absorbances and the concentrations of the investigated drugs in the range of 4–120 μg/mL. The limits of detection for the assays ranged from 1.19 to 2.98 μg/mL. The precision values of the methods were satisfactory; the relative standard deviations were 0.56–1.24%. The proposed methods were successfully applied to the determination of the 3 drugs in pure and pharmaceutical dosage forms with good accuracy; the recoveries ranged from 99.1 to 101.3% with standard deviations of 1.15–1.92%. The results compared favorably with those of reported methods.

Simultaneous Determination of Sildenafil and Tadalafil in Legal Drugs, Illicit/Counterfeit Drugs, and Wastewater Samples by High-Performance Liquid Chromatography

2016 ◽  
Vol 99 (4) ◽  
pp. 923-928 ◽  
Author(s):  
Ali Kemal Fidan ◽  
Sezgin Bakirdere
Keyword(s):  
Simultaneous Determination ◽  
High Performance ◽  
Quantitative Measurement ◽  
Correlation Coefficients ◽  
Wastewater Sample ◽  
Counterfeit Drugs ◽  
Spiking Experiment ◽  
Wastewater Samples ◽  
Erectile Dysfunction Drug

Abstract A sensitive analytical method was developed for the simultaneous determination of sildenafil and tadalafil in legal drugs, illicit/counterfeit drugs, and wastewater samples. Chromatographic separation of two analytes was achieved on a C18 column with a mobile phase including 50 mM phosphate buffer at pH 6.0 and acetonitrile (35 + 65, v/v) at the flow rate of 1.0 mL/min. Analytes were separated from each other in 6 min with high resolution. LOD/LOQ values were calculated as 28/92 ng/mL for sildenafil citrate and 39/129 ng/mL for tadalafil. Calibration plots for both analytes were linear with correlation coefficients &gt;0.9993. A validated method was successfully applied to legal and illicit erectile-dysfunction drug samples consumed in Istanbul, Turkey, and to wastewater samples. Nine different samples were analyzed for qualitative and quantitative measurement of their ingredients, and the results were compared with the values written on the labels of the drugs. The wastewater sample was also analyzed for its sildenafil and tadalafil content. To calculate the recoveries, a spiking experiment was performed and recovery rates for sildenafil and tadalafil were calculated as 101.30 ± 3.43 and 102.68 ± 1.59, respectively.

scholarly journals Papers read to the Society, February 17, 1898

1898 ◽  
Vol 62 (379-387) ◽  
pp. 385-385
Keyword(s):  
Chemical Composition ◽  
Electrical Properties ◽  
Mathematical Theory ◽  
Cephalic Index ◽  
Theory Of Evolution ◽  
Colour Blindness ◽  
Elasmobranch Fishes

I. “On the Connection between the Electrical Properties and the Chemical Composition of different kinds of Glass.” By Professor Andrew Gray, LL.D., F. R. S., and Professor J. J. Bobbie, M.A., D.Sc. II. “On the Magnetic Deformation of Nickel.” By E. Taylor Jones, D.Sc. Communicated by Professor Andrew Gray, F. R. S. III. “Upon the Structure and Development of the Enamel of Elasmobranch Fishes.” By Charles S. Tomes, M.A., F. R. S. V. “On artificial temporary Colour-blindness, with an Examination of the Colour Sensations of 109 Persons.” By George J. Burch, M.A. Communicated by Professor Gotch, F. R. S. V. “Contributions to the Mathematical Theory of Evolution. On the Inheritance of the Cephalic Index.” By Cicely Fawcett and Karl Pearson, F. R. S.

Sign in / Sign up

Export Citation Format

Share Document