scholarly journals On the Standard Errors in the Fitting of Polynomials to Unequally Spaced Observations

1953 ◽  
Vol 6 (2) ◽  
pp. 131 ◽  
Author(s):  
PG Guest
Keyword(s):  
Least Squares ◽  
Standard Errors ◽  
The Third ◽  
Unequally Spaced ◽  
Uniform Spacing ◽  
Independent Variable ◽  
Two Parameters ◽  
Second Degree

From the observed values of the independent variable two parameters are derived which specify the departure from uniform spacing. Expressions are obtained for the standard errors of the coefficients and fitted values in terms of these parameters, and numerical tables for the estimation of the errors are given. It is shown that the errors calculated in this way lie within a few per cent. of the exact least squares values for polynomials of the first and second degree, but when the polynomial is of the third degree the deviations may be much greater.

scholarly journals Efficiencies in the Method of Grouping

1953 ◽  
Vol 6 (4) ◽  
pp. 361
Author(s):  
PG Guest
Keyword(s):  
Curve Fitting ◽  
Degree Polynomial ◽  
The Third ◽  
Uniform Spacing ◽  
Two Parameters ◽  
Second Degree

The efficiencies obtained in curve fitting by the method of grouping are discussed in terms of two parameters x2 x3 which specify the departure from uniform spacing. For polynomials of the first and second degree the efficiencies practically always exceed 0�7, but the efficiencies for the third degree polynomial may be less than this value if the spacing is markedly non-uniform.

PENGARUH PEMANFAATAN TEKNOLOGI INFORMASI TERHADAP KEPUASAN END USER COMPUTING DENGAN KETIDAKPASTIAN TUGAS SEBAGAI VARIABEL MODERATING

2013 ◽  
Author(s):  
Herawati M
Keyword(s):  
Information Technology ◽  
Primary Data ◽  
End User ◽  
Moderating Variables ◽  
The Third ◽  
Use Of Technology ◽  
Task Uncertainty ◽  
Independent Variable ◽  
The City ◽  
End User Computing

This study aims to use information technology, uncertainty or moderation duties and interactions between task uncertainty with the use of information technology to end user computing satisfaction. In this study used 70 respondents who actively use computers and working with several companies banking on the city of Padang. The data used are the primary data obtained through questionnaires. The study used three types of variables, the first is the independent variable, namely the utilization of information technology, both moderating variables, namely the uncertainty of the task, the third is the dependent variable is satisfaction of end user computing. The stages of hypothesis testing is done by using a regression model of moderating and statistical t-test. Based on the results of testing the first hypothesis (HI) was found to significantly influence the utilization of information technology to the satisfaction of end user computing. The second hypothesis (H2) testing results found that task uncertainty did not significantly influence the end user computing satisfaction. The third hypothesis (H3) testing found that the interaction or moderation between the use of technology with task uncertainty no significant effect on end user computing satisfaction.

Comparison of plasma progesterone profiles in cyclic, pregnant, pseudopregnant and hysterectomized pigs between 8 and 27 days after oestrus

1988 ◽  
Vol 119 (1) ◽  
pp. 111-116 ◽  
Author(s):  
G. J. King ◽  
R. Rajamahendran
Keyword(s):  
Least Squares ◽  
Analysis Of Variance ◽  
The Other ◽  
Corpora Lutea ◽  
Plasma Progesterone ◽  
The Third ◽  
Secretory Potential ◽  
The Mean

ABSTRACT Plasma progesterone concentrations were compared in cyclic (n = 12), pregnant (n =12), oestradiol-induced pseudopregnant (n=12) and hysterectomized gilts (n=10) between days 8 and 27 after oestrus. The results were grouped into periods covering days 8–13, 14–20 and 21–27 and analysed by least-squares analysis of variance. Plasma progesterone concentrations were significantly (P<0·001) higher in hysterectomized compared with other groups between days 8 and 13. Progesterone concentrations declined rapidly after day 14 in cyclic females and gradually in the other groups. Throughout the third and fourth weeks the mean progesterone concentrations for hysterectomized animals were consistently higher than for pseudopregnant animals (P<0·05). The pregnant group means were below but not significantly different from the hysterectomized means in both of the last two periods. The greater progesterone concentrations in hysterectomized gilts indicated that secretion is high without any conceptus-produced or -mediated luteotrophin, and corpora lutea in cyclic, pregnant or pseudopregnant gilts may never reach full secretory potential. J. Endocr. (1988) 119, 111–116

scholarly journals Foreign Direct Investment, Natural Resources, Economic Freedom, and Sea-Access: Evidence from the Commonwealth of Independent States

2020 ◽  
Vol 12 (8) ◽  
pp. 3135 ◽  
Author(s):  
Wencong Lu ◽  
Ikboljon Kasimov ◽  
Ibrokhim Karimov ◽  
Yakhyobek Abdullaev
Keyword(s):  
Foreign Direct Investment ◽  
Natural Resources ◽  
Least Squares ◽  
Random Effects ◽  
Direct Investment ◽  
Economic Freedom ◽  
Generalized Least Squares ◽  
Standard Errors ◽  
Fdi Inflows ◽  
Independent States

This study examines the importance of natural resources, economic freedom, and sea-access in attracting foreign direct investment (FDI) inflows to the Commonwealth of Independent States (CIS), using panel data from 1998 to 2017. The Prais-Winsten regression with panel-corrected standard errors (PCSEs) is employed for all estimations. Feasible Generalized Least Squares (FGLS), Random Effects with Driscoll-Kraay standard errors (RE (D-K)), and Random Effects of Generalized Least Squares (RE (GLS)) estimators are used to test the sensitivity of PCSEs’ estimates to changes in the underlying empirical model, whereas Instrumental Variables with Two Stage Least Squares (IV (2SLS)), Limited Information Maximum Likelihood (LIML), and Baltagi’s Two-Stage Least-Squares Random-Effects (IV (EC2SLS)) estimators are used to address potential endogeneity concerns. The estimates confirm that natural resources, economic freedom, and sea-access are robust and decisive factors affecting FDI location decisions of foreign investors in CIS. More precisely, the results suggest that increased revealed comparative advantage in petroleum, higher economic freedom characterized by the increased government size and open markets, and territorial coastlines have a statistically significant and positive effect on FDI inflows to CIS transition economies. We also find that direct access to the Black Sea and the Caspian Sea provides a significant geographic competitive advantage to Azerbaijan, Kazakhstan, Georgia, Russia, Turkmenistan, and Ukraine in attracting FDI inflows over the other CIS member-states.

scholarly journals Analysis of algebraic weighted least-squares estimators for enzyme parameters

1992 ◽  
Vol 288 (2) ◽  
pp. 533-538 ◽  
Author(s):  
M E Jones
Keyword(s):  
Least Squares ◽  
Coefficient Of Variation ◽  
Constant Coefficient ◽  
Weighted Least Squares ◽  
Simulated Data ◽  
Standard Errors ◽  
Parameter Estimates ◽  
Spreadsheet Program ◽  
Least Squares Estimators ◽  
Constant Coefficient Of Variation

An algorithm for the least-squares estimation of enzyme parameters Km and Vmax. is proposed and its performance analysed. The problem is non-linear, but the algorithm is algebraic and does not require initial parameter estimates. On a spreadsheet program such as MINITAB, it may be coded in as few as ten instructions. The algorithm derives an intermediate estimate of Km and Vmax. appropriate to data with a constant coefficient of variation and then applies a single reweighting. Its performance using simulated data with a variety of error structures is compared with that of the classical reciprocal transforms and to both appropriately and inappropriately weighted direct least-squares estimators. Three approaches to estimating the standard errors of the parameter estimates are discussed, and one suitable for spreadsheet implementation is illustrated.

scholarly journals ALOE VERA VS. SILVER SULFADIAZINE FOR TREATING SECOND-DEGREE BURN WOUNDS: EVIDENCE-BASED CASE REPORT

2019 ◽  
pp. 146-148
Author(s):  
CLARA MENNA ◽  
NABILLA CALISTA ◽  
LEORCA AURINO ◽  
ADISTI DWIJAYANTI
Keyword(s):  
Clinical Trials ◽  
Risk Reduction ◽  
Randomized Clinical Trials ◽  
Aloe Vera ◽  
Silver Sulfadiazine ◽  
Number Needed To Treat ◽  
Burn Wounds ◽  
The Third ◽  
Degree Burn ◽  
Second Degree

Objective: Current treatment for second-degree burn wounds, including silver sulfadiazine (SSD) application, may cause side effects such as delayed and incomplete wound healing, leaving a scar. Traditional plants empirically used for burn wounds, such as Aloe vera, seem to be a promising option with good safety profiles. Methods: We therefore compared Aloe vera to SSD for second-degree burn wounds based on a review of clinical trials obtained by an organized search through the Cochrane, PubMed, and DynaMed databases. Three randomized clinical trials studies were selected, two of which were critically appraised. The third study, with a different outcome assessment, was analyzed separately. Results: Two studies showed that Aloe vera was more effective in treating second-degree burn wounds than SSD 1% with an absolute risk reduction of 0.2, relative risk reduction of 0.83–1.0, and number needed to treat five patients. The Aloe vera group showed faster healing, earlier epithelialization, and earlier pain alleviation. The third study combined Aloe vera with other herbs, which showed better healing ability and restored skin hydration than those with SSD. Conclusion: Each of the three articles stated that Aloe vera was more effective than SSD for treating second-degree burn wounds. Nevertheless, each of the studies lacked methodology and comprehensive data reporting.

Characteristics of statistical parameters used to interpret least-squares results.

1978 ◽  
Vol 24 (4) ◽  
pp. 611-620 ◽  
Author(s):  
R B Davis ◽  
J E Thompson ◽  
H L Pardue
Keyword(s):  
Experimental Data ◽  
Least Squares ◽  
Confidence Intervals ◽  
Standard Error ◽  
Statistical Parameters ◽  
Average Value ◽  
Data Points ◽  
Independent Variable ◽  
Highly Correlated

Abstract This paper discusses properties of several statistical parameters that are useful in judging the quality of least-squares fits of experimental data and in interpreting least-squares results. The presentation includes simplified equations that emphasize similarities and dissimilarities among the standard error of estimate, the standard deviations of slopes and intercepts, the correlation coefficient, and the degree of correlation between the least-squares slope and intercept. The equations are used to illustrate dependencies of these parameters upon experimentally controlled variables such as the number of data points and the range and average value of the independent variable. Results are interpreted in terms of which parameters are most useful for different kinds of applications. The paper also includes a discussion of joint confidence intervals that should be used when slopes and intercepts are highly correlated and presents equations that can be used to judge the degree of correlation between these coefficients and to compute the elliptical joint confidence intervals. The parabolic confidence intervals for calibration cures are also discussed briefly.

scholarly journals A New Concept in Calculation of Thick Film Resistors

1977 ◽  
Vol 4 (3-4) ◽  
pp. 163-169 ◽  
Author(s):  
G. Stecher
Keyword(s):  
Process Control ◽  
Film Thickness ◽  
Least Squares ◽  
Thick Film ◽  
Test Pattern ◽  
Process Conditions ◽  
Computer Programme ◽  
Method Of Least Squares ◽  
Computer Plot ◽  
Two Parameters

Because of interaction of resistor and conductor material and variation of film thickness due to different resistor geometries, square resistance becomes a function of resistor length and width. Additional to the square resistance one paste parameter or two parameters must be introduced if the influence of both length and width on the square resistance is to be taken into account. From resistance measurements of a test pattern all paste parameters can be calculated as numerical functions of resistor length by a computer programme using the method of least squares. Beside the layout of thick film resistors, the data are suitable to give a computer plot of square resistance in relation to length and width. This representation can play an important part in paste evaluation and process control. It shows at a glance what relationship will be present with various combinations of conductor and resistor materials or by changed process conditions.

APPROXIMATION TO THE LATERAL VARIATION OF RESIDUAL GRAVITY DUE TO A FRUSTUM OF A VERTICAL CONE

Geophysics ◽  
1953 ◽  
Vol 18 (2) ◽  
pp. 401-415
Author(s):  
W. Raymond Griffin
Keyword(s):  
Gulf Coast ◽  
Lateral Variation ◽  
Vertical Cone ◽  
Salt Domes ◽  
Residual Gravity ◽  
Special Cases ◽  
Lateral Distance ◽  
Independent Variable ◽  
The Subject ◽  
Two Parameters

The equation for the subject title is presented in nondimensional form. The approximation consists of considering a frustum of a vertical cone in which the radii are small relative to the depth to its top. The dependent variable has been taken as being the ratio of the residual gravity (as defined in a previous publication by the author) to the maximum residual gravity. The independent variable was chosen as the ratio of the lateral distance (from the center line of the frustum to a given station) to the depth to the top of the frustum. The two parameters were chosen as being (a) The ratio of depth to the bottom of the frustum to that to its top, (b) The ratio of the bottom radius to that of the top radius. It is then shown that, for special values of the parameters, the equation gives the lateral variation of residual gravity due to cylinders, upright cones, and inverted cones as special cases. Tables of the principal functions, which occur in the equation, are given over practical ranges of values. Graphs of the equation are given. They cover the practical range for each of the variables and each of the parameters. Application of the equation is made to two Gulf Coast salt domes whose dimensions are rather well known from previous drilling. Graphs, showing the degree of correlation, are given. The conclusion is drawn that, despite the approximation involved in the derivation of the equation, and despite the departure of the ratio of the dimensions of the salt domes from that assumed, the correlation with the actual gravity values for two deep salt domes is remarkably close.

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