Beta Standard Error Regression
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Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack standard error of coefficient in linear regression Overflow the company Business Learn more about hiring developers or posting ads with us standard error of beta hat Cross Validated Questions Tags Users Badges Unanswered Ask Question _ Cross Validated is a question and answer site for people interested standard error of coefficient multiple regression in statistics, machine learning, data analysis, data mining, and data visualization. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are what does standard error of coefficient mean voted up and rise to the top How to derive the standard error of linear regression coefficient up vote 2 down vote favorite 3 For this univariate linear regression model $$y_i = \beta_0 + \beta_1x_i+\epsilon_i$$ given data set $D=\{(x_1,y_1),...,(x_n,y_n)\}$, the coefficient estimates are $$\hat\beta_1=\frac{\sum_ix_iy_i-n\bar x\bar y}{n\bar x^2-\sum_ix_i^2}$$ $$\hat\beta_0=\bar y - \hat\beta_1\bar x$$ Here is my question, according to the book and Wikipedia, the standard error of $\hat\beta_1$ is $$s_{\hat\beta_1}=\sqrt{\frac{\sum_i\hat\epsilon_i^2}{(n-2)\sum_i(x_i-\bar x)^2}}$$ How and
Standard Error Of Beta Linear Regression
why? standard-error inferential-statistics share|improve this question edited Mar 6 '15 at 14:38 Christoph Hanck 9,02332148 asked Feb 9 '14 at 9:11 loganecolss 5431926 stats.stackexchange.com/questions/44838/… –ocram Feb 9 '14 at 9:14 @ocram, thanks, but I'm not quite capable of handling matrix stuff, I'll try. –loganecolss Feb 9 '14 at 9:20 1 @ocram, I've already understand how it comes. But still a question: in my post, the standard error has $(n-2)$, where according to your answer, it doesn't, why? –loganecolss Feb 9 '14 at 9:40 add a comment| 1 Answer 1 active oldest votes up vote 7 down vote accepted 3rd comment above: I've already understand how it comes. But still a question: in my post, the standard error has (n−2), where according to your answer, it doesn't, why? In my post, it is found that $$ \widehat{\text{se}}(\hat{b}) = \sqrt{\frac{n \hat{\sigma}^2}{n\sum x_i^2 - (\sum x_i)^2}}. $$ The denominator can be written as $$ n \sum_i (x_i - \bar{x})^2 $$ Thus, $$ \widehat{\text{se}}(\hat{b}) = \sqrt{\frac{\hat{\sigma}^2}{\sum_i (x_i - \bar{x})^2}} $$ With $$ \hat{\sigma}^2 = \frac{1}{n-2} \sum_i \hat{\epsilon}_i^2 $$ i.e. the Mean Square Error (MSE) in the ANOVA table, we end up with your expression for $\widehat{\text{se}}(\hat{b})$. The $n-2$ term accounts for the loss of 2 degrees of freedom in the estimation of
The standard error of the coefficient is always positive. Use the standard error of the coefficient to measure the precision of the estimate of
Standard Error Of Beta Coefficient Formula
the coefficient. The smaller the standard error, the more precise the standard error of regression coefficient excel estimate. Dividing the coefficient by its standard error calculates a t-value. If the p-value associated with this standard error of regression coefficient calculator t-statistic is less than your alpha level, you conclude that the coefficient is significantly different from zero. For example, a materials engineer at a furniture manufacturing site wants http://stats.stackexchange.com/questions/85943/how-to-derive-the-standard-error-of-linear-regression-coefficient to assess the strength of the particle board that they use. The engineer collects stiffness data from particle board pieces with various densities at different temperatures and produces the following linear regression output. The standard errors of the coefficients are in the third column. Coefficients Term Coef SE Coef T-Value P-Value VIF Constant 20.1 12.2 http://support.minitab.com/en-us/minitab/17/topic-library/modeling-statistics/regression-and-correlation/regression-models/what-is-the-standard-error-of-the-coefficient/ 1.65 0.111 Stiffness 0.2385 0.0197 12.13 0.000 1.00 Temp -0.184 0.178 -1.03 0.311 1.00 The standard error of the Stiffness coefficient is smaller than that of Temp. Therefore, your model was able to estimate the coefficient for Stiffness with greater precision. In fact, the standard error of the Temp coefficient is about the same as the value of the coefficient itself, so the t-value of -1.03 is too small to declare statistical significance. The resulting p-value is much greater than common levels of α, so that you cannot conclude this coefficient differs from zero. You remove the Temp variable from your regression model and continue the analysis. Why would all standard errors for the estimated regression coefficients be the same? If your design matrix is orthogonal, the standard error for each estimated regression coefficient will be the same, and will be equal to the square root of (MSE/n) where MSE = mean square error and n = number of observations.Minitab.comLicense PortalStoreBlogContact UsCopyright © 2016 Minita
article by introducing more precise citations. (January 2010) (Learn how and when to remove this template message) Part of https://en.wikipedia.org/wiki/Simple_linear_regression a series on Statistics Regression analysis Models Linear regression Simple regression Ordinary least squares Polynomial regression General linear model Generalized linear model Discrete choice Logistic regression Multinomial logit Mixed logit Probit Multinomial probit Ordered logit Ordered probit Poisson Multilevel model Fixed effects Random effects Mixed model Nonlinear regression Nonparametric Semiparametric Robust Quantile Isotonic standard error Principal components Least angle Local Segmented Errors-in-variables Estimation Least squares Ordinary least squares Linear (math) Partial Total Generalized Weighted Non-linear Non-negative Iteratively reweighted Ridge regression Least absolute deviations Bayesian Bayesian multivariate Background Regression model validation Mean and predicted response Errors and residuals Goodness of fit Studentized residual Gauss–Markov theorem Statistics portal v t e standard error of Okun's law in macroeconomics is an example of the simple linear regression. Here the dependent variable (GDP growth) is presumed to be in a linear relationship with the changes in the unemployment rate. In statistics, simple linear regression is the least squares estimator of a linear regression model with a single explanatory variable. In other words, simple linear regression fits a straight line through the set of n points in such a way that makes the sum of squared residuals of the model (that is, vertical distances between the points of the data set and the fitted line) as small as possible. The adjective simple refers to the fact that the outcome variable is related to a single predictor. The slope of the fitted line is equal to the correlation between y and x corrected by the ratio of standard deviations of these variables. The intercept of the fitted line is such that it passes through the cen