C index in r
The Herfindahl-Hirschman Index (HHI) is a widely used measure of market concentration. The HHI is calculated by squaring the market share of each firm in the industry and summing the result: HHI = s1^2 + s2^2 + s3^2 + + sn^2 where s is the market share of each firm. The HHI is used as a measure We retrieve values in a vector by declaring an index inside a single square bracket "[]" operator.. For example, the following shows how to retrieve a vector member. Since the vector index is 1-based, we use the index position 3 for retrieving the third member. CDC Museum — see CDC Museum, David J. Sencer: In Association with the Smithsonian Institution — see Museum, CDC. What is the A-Z Index? What items are included? Why is there more than one A-Z Index? Can I suggest a new entry? Function and Macro Index. Jump to: * _ A B C D E F G H I J K L M N O P Q R S T U V W Y R’s C interface Reading R’s source code is an extremely powerful technique for improving your programming skills. However, many base R functions, and many functions in older packages, are written in C.
29 Dec 2016 Keywords Biomarkers, C-index, discrimination, Pareto model, Some have attempted to transfer the concept of R2 from linear regression to
Unlike in some other programming languages, when you use negative numbers for indexing in R, it doesn’t mean to index backward from the end. Instead, it means to drop the element at that index, counting the usual way, from the beginning. The C-statistic (sometimes called the “concordance” statistic or C-index) is a measure of goodness of fit for binary outcomes in a logistic regression model. In clinical studies, the C-statistic gives the probability a randomly selected patient who experienced an event (e.g. a disease or condition) had a higher risk score than a patient who had not experienced the event. R has overloaded the double equals == operator with a method of finding the index of a needle in a vector haystack. It yields a logical vector, containing TRUE values for each match in the haystack. Example: haystack <- c(1, 2, 4, 3, 4) needle <- 4 indices <- needle == haystack indices [1] 3 5 haystack[indices] [1] 4 4 Firearms automatically attain C&R status when they are 50 years old. Any firearm that is at least 50 years old, and in its original configuration, would qualify as a C&R firearm. It is not necessary for such firearms to be listed in ATF's C&R list. Therefore, ATF does not generally list firearms in the C&R publication by virtue of their age. www.crlaurence.com The Herfindahl-Hirschman Index (HHI) is a widely used measure of market concentration. The HHI is calculated by squaring the market share of each firm in the industry and summing the result: HHI = s1^2 + s2^2 + s3^2 + + sn^2 where s is the market share of each firm. The HHI is used as a measure We retrieve values in a vector by declaring an index inside a single square bracket "[]" operator.. For example, the following shows how to retrieve a vector member. Since the vector index is 1-based, we use the index position 3 for retrieving the third member.
We retrieve values in a vector by declaring an index inside a single square bracket "[]" operator.. For example, the following shows how to retrieve a vector member. Since the vector index is 1-based, we use the index position 3 for retrieving the third member.
17 Apr 2007 Discrimination; Concordance; C-Statistic; C-Index; Survival; Time- where Q, R and S are the number of terms in the respective summations. 10 Sep 2013 Abstract. Objective: The concordance index (c-index) is the standard way of evalu - ating the performance of c-index score as the Cox model (c-index = 0.70 and 0.71 respectively) on the cancer test set. R environment. 16 12 Nov 2015 Re: How to get c-statistics (c-index, concordance) from Proc Phreg for Logistic and it is also known as 'concordance' in R 'survival' package. probability (C-index) is the frequency of concordant pairs among all pairs of subjects. It can be used to measure and compare the discriminative power of a risk prediction models. The function provides an inverse of the probability of censoring weigthed estimate of the concordance probability to adjust for right censoring. C-index for survival analysis with confidence interval (R) I have tried now several packages in R for Cox proportional hazard regression and I am having a hard time to find a function where I can fit a model using cross validation/bootstrapping and obtain an estimate of the C-index based on the untrained items with a confidence interval. R - differences between cindex function from pec package and coxph. Ask Question Asked 5 years, 4 months ago. It looks like ties are handled differently by default when computing the C-index between these two. Formula in coxph (see ?survConcordance()): (agree + tied/2)/(agree + disagree + tied). Description Proposed by Harrell, the C index or concordance C, is considered an overall mea- sure of discrimination in survival analysis between a survival outcome that is possibly right cen- sored and a predictive-score variable, which can represent a measured biomarker or a composite-
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The C-statistic (sometimes called the “concordance” statistic or C-index) is a measure of goodness of fit for binary outcomes in a logistic regression model. In clinical studies, the C-statistic gives the probability a randomly selected patient who experienced an event (e.g. a disease or condition) had a higher risk score than a patient who had not experienced the event. R has overloaded the double equals == operator with a method of finding the index of a needle in a vector haystack. It yields a logical vector, containing TRUE values for each match in the haystack. Example: haystack <- c(1, 2, 4, 3, 4) needle <- 4 indices <- needle == haystack indices [1] 3 5 haystack[indices] [1] 4 4 Firearms automatically attain C&R status when they are 50 years old. Any firearm that is at least 50 years old, and in its original configuration, would qualify as a C&R firearm. It is not necessary for such firearms to be listed in ATF's C&R list. Therefore, ATF does not generally list firearms in the C&R publication by virtue of their age. www.crlaurence.com
R has overloaded the double equals == operator with a method of finding the index of a needle in a vector haystack. It yields a logical vector, containing TRUE values for each match in the haystack. Example: haystack <- c(1, 2, 4, 3, 4) needle <- 4 indices <- needle == haystack indices [1] 3 5 haystack[indices] [1] 4 4
This function calculates Harrell's c-index. View source: R/cindex.r total. The total number of pairs that can be evaluated. cindex. Harrell's c-index Re: 1) coxph::concordance differs from pec::cindex. It looks like ties are handled differently by default when computing the C-index between 28 Jan 2015 Description Proposed by Harrell, the C index or concordance C, is considered an overall mea- R topics documented: compareC . 22 Dec 2016 R topics documented: cindex . 2 cindex cindex. Method to extract the estimated generalized c-index from a concreg object. Description. I'd like to be able to calculate the C-statistic/C-index for my proc phreg model. Does the concordance index in the R Survival package test the model on the 1 Feb 2017 The simplest way to get empirically based confidence intervals is bootstrapping. If you do 999 bootstraps and rank your statistic of interest in 2.2 Computing concordance index, D index and hazard ratio . . . . . . . . . . . x.se= cbind (cindexall.mainz.small[i,"cindex.se"],. + r.mean <- c(NA,ccindex$cindex). >
Function and Macro Index. Jump to: * _ A B C D E F G H I J K L M N O P Q R S T U V W Y R’s C interface Reading R’s source code is an extremely powerful technique for improving your programming skills. However, many base R functions, and many functions in older packages, are written in C.