Tag: regression

Feed: R-bloggers. Author: ApokalypsePartyTeam. In a hospital, 9% of all patients have Covid-19. But: Among the heavy smokers among these patients, only 6% have Covid-19. What? Does smoking reduce your risk of getting Covid? Another example: I recently saw a post on Twitter with a line graph showing that, in the UK, persons aged 18 to 59 who were vaccinated against the coronavirus had a higher risk of dying (from any cause) in the next 21 days as opposed to unvaccinated persons aged 18 to 59. Does the vaccine increase your chance of dying? The answers to these questions can ... Read More

Feed: R-bloggers. Author: sang-heon lee.   #———————————————–  # F test by using linearHypothesis()  #———————————————–  # H0 : b2/b1 = Nelson-Siegel slope factor  #      b3/b1 = Nelson-Siegel curvature factor  #———————————————–    NS_slope – (1–exp(–lambda*tau))/(lambda*tau)    NS_curvature – NS_slope – exp(–lambda*tau)    H0 – c(paste0(“slope_can=”,NS_slope,“*level_can”),             paste0(“curvature_can=”,NS_curvature,“*level_can”))    # F test for coefficients restrictions    linearHypothesis(reg.U, H0)  #———————————————–  # F test by mannual calculation  #———————————————–  # H0 : b2/b1 = Nelson-Siegel slope factor  #      b3/b1 = Nelson-Siegel curvature factor  #———————————————–    # restricted regression model    reg.R – lm(exr_can3 ~ I(level_can +                     NS_slope*slope_can +                     NS_curvature*curvature_can),                 data = df.data, na.action = na.omit)    # input variables for F-test    T – length(reg.U$residuals)    # # of observations    K – length(reg.U$coefficients) # # of parameters    J – 2                          # # of restrictions      # residual sum of squares    RSSU – sum(reg.U$residuals^2)    RSSR – sum(reg.R$residuals^2)    # calculated F-test statistic    F_test – ((RSSR – RSSU)/J)/(RSSU/(T–K))    # 95% critical value and p-value    qf(.95, df1=J, df2=(T–K))        # 95% critical value    1 – pf(F_test, df1=J, df2=(T–K)) # p-value ... Read More

Feed: R-bloggers. Author: Selcuk Disci. [This article was first published on DataGeeek, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. Huge lines at gas stations have been seen around Turkey in recent days. Under the reason for this is the rise in the prices so often, in the last few months and the expectation to continue this. Of course, it is known that the rise in the exchange rate (US dollar to Turkish ... Read More

Feed: Planet PostgreSQL. 1. Overview I have been working on an internal project based on PostgreSQL for a while, and from time to time, I need to run some specific test cases to verify my changes. Here, I want to shared a tip to run a specific regression TAP test quickly, especially, when you are focusing on a particular bug and you know which test case can help verify the fix. A details document about the regression test can be found at Running the Tests. 2. Regression test PostgreSQL provides a comprehensive set of regression tests to verify the SQL ... Read More

Feed: R-bloggers. Author: finnstats. [This article was first published on Methods – finnstats, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. finnstats can help you improve your data abilities and advance your profession. Homoscedasticity in Regression Analysis, The Goldfeld–Quandt test checks for homoscedasticity in regression studies in statistics. Subscribe This is accomplished by separating a dataset into two portions or groups, which is why the test is also known as a two-group test ... Read More

Feed: R-bloggers. Author: finnstats. [This article was first published on Methods – finnstats, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. Regression in R, In a recent article, we discussed model fitting and selection. However, we haven’t considered how we’ll choose which variables to include in our model. Simple Linear Regression in r » Guide » Let’s go over our linear regression model for the mtcars data.frame again. Regression in R mtcars.lm <- ... Read More

Feed: SAS Blogs. Author: Rick Wicklin. It can be frustrating when the same probability distribution has two different parameterizations, but such is the life of a statistical programmer. I previously wrote an article about the gamma distribution, which has two common parameterizations: one that uses a scale parameter (β) and another that uses a rate parameter (c = 1/β). The relationship between scale and rate parameters is straightforward, but sometimes the relationship between different parameterizations is more complicated. Recently, a SAS programmer was using a regression procedure to fit the parameters of a Weibull distribution. He was ... Read More

Feed: R-bloggers. Author: Selcuk Disci. [This article was first published on DataGeeek, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. The higher education students have had trouble being housing in Turkey in recent days. There have been people who even sleep on the streets like a homeless. The government has been accused of investing inadequate dormitories for sheltering the students. Let’s examine the ongoing sheltering problem of students. The dataset we have built ... Read More

Feed: R-bloggers. Author: finnstats. [This article was first published on Methods – finnstats, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. Simple linear regression in r, we want to create models to investigate and forecast the relationship between variables, and the most basic relationship that we can think of is a straight line. Visit finnstats.com for up-to-date and accurate lessons. Let’s take a look at the first linear relationship that we are going ... Read More

Feed: R-bloggers. Author: T. Moudiki. Last week I presented ahead, an R package for univariate and multivariate time series forecasting. In particular, the function dynrmf was introduced for univariate time series, with examples of Random Forest and Support Vector Machines fitting functions (fitting and predicting through fit_func and predict_func arguments of dynrmf). First things first, here’s how to install R package ahead: 1st method: from R-universe In R console: options(repos = c( techtonique = 'https://techtonique.r-universe.dev', CRAN = 'https://cloud.r-project.org')) install.packages("ahead") 2nd method: from Github In R console: devtools::install_github("Techtonique/ahead") Or remotes::install_github("Techtonique/ahead") In version 0.2.0 of ahead, Ridge regression is the default fitting ... Read More