Semiparametrically efficient estimation of the average linear regression function

Based on experimental results of uniaxial compression and short-term creep using 8-step loading-unloading method, fine sandstone specimen, which lower creep limit is 27MPa, present typical brittle breakage properties of hard rock. The correlative coefficients of linear regression function for isochronous stress-strain curve are all higher than 0. 92, and the ratio of long-term strength to instantaneous strength reaches 94. 39%，which indicate that the whole creep of fine sandstone specimen is weak. The average correlative coefficients of linear regression function for isochronous stress- axial strain curve are 3. 92% higher than that of average correlative coefficients of linear regression function for isochronous stress- radial strain curve, so nonlinear creep property of the fine sandstone specimen in axial direction is correspondingly weaker than that in radial direction. Negative Gauss distribution can be applied collectively to nonlinear creep of fine sandstone specimen, which has obvious time effect.With increasing loading, the reduction degrees of average correlative coefficients of linear fitting functions of isochronous stress-axial strain curve and isochronous stress-radial strain curve are 0. 97% and 0. 67% respectively, which indicates the linear correlation decreases commonly. Thus, the degree of nonlinear creep for fine sandstone specimen increases along with loading stress with obvious stress effect.

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Temperature dependence of blood surface tension

Physiological Research ◽

10.33549/physiolres.931306 ◽

2007 ◽

pp. S93-S98

Author(s):

J Rosina ◽

E Kvašňák ◽

D Šuta ◽

H Kolářová ◽

J Málek ◽

...

Keyword(s):

Surface Tension ◽

Linear Regression ◽

Blood Serum ◽

Whole Blood ◽

Healthy Subjects ◽

Regression Function ◽

Sediment Surface ◽

Linear Regression Equation ◽

Linear Regression Function ◽

Ring Method

Whole blood surface tension of 15 healthy subjects recorded by the ring method was investigated in the temperature range from 20 to 40 degrees C. The surface tension omega as a function of temperature t ( degrees C) is described by an equation of linear regression as omega(t) = (-0.473 t + 70.105) x 10(-3) N/m. Blood serum surface tension in the range from 20 to 40 degrees C is described by linear regression equation omega(t) = (-0.368 t + 66.072) x 10(-3) N/m and linear regression function of blood sediment surface tension is omega(t) = (-0.423 t + 67.223) x10(-3) N/m.

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METODA ZANURZANIA REGRESJI W PRZYPADKU WYSTĘPOWANIA OBSERWACJI NIETYPOWYCH

Metody Ilościowe w Badaniach Ekonomicznych ◽

10.22630/mibe.2019.20.2.9 ◽

2019 ◽

Vol 20 (2) ◽

pp. 83-92

Author(s):

Małgorzata Kobylińska

Keyword(s):

Linear Regression ◽

Least Squares ◽

Least Squares Method ◽

Regression Function ◽

Maximum Depth ◽

Two Dimensional ◽

Structural Elements ◽

Linear Regression Function ◽

Regression Functions

This paper presents the application of the regression maximum depth for the estimation of linear regression function structural elements. For two-dimensional sets including untypical observations, regression functions were developed using the classical least squares method and a method based on the concept of observation depth measure in a sample. The effect of untypical observations on the estimated models has been noted.

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