What is C-statistic in logistic regression?

What is C-statistic in logistic regression?

What is a C-Statistic? The concordance statistic is equal to the area under a ROC curve. 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.

What is good C-statistic?

Glossary Definition Models are typically considered reasonable when the C-statistic is higher than 0.7 and strong when C exceeds 0.8 (Hosmer & Lemeshow, 2000; Hosmer & Lemeshow, 1989).

Is C-statistic same as AUC?

Harrel’s concordance index C is defined as the proportion of observations that the model can order correctly in terms of survival times. When censoring is observed the statistic only includes those patient pairs for which valid comparisons can be made. Sometimes C is called the AUC.

What is Harrell’s C statistic?

Harrell’s C-index (also known as the concordance index) introduced in Harrell et al. 1982, is a goodness of fit measure for models which produce risk scores. It is commonly used to evaluate risk models in survival analysis, where data may be censored.

How do you find C statistic?

The c-statistic is equal to the AUC (area under the curve), and can also be calculated by taking all possible pairs of individuals consisting of one individual who experienced a positive outcome and one individual who experienced a negative outcome.

How is AUC determined?

The area under the plasma drug concentration-time curve (AUC) reflects the actual body exposure to drug after administration of a dose of the drug and is expressed in mg*h/L. This area under the curve is dependant on the rate of elimination of the drug from the body and the dose administered.

When do you use a logistic regression method?

Logistic Regression is a statistical method that we use to fit a regression model when the response variable is binary. Here are some examples of when we may use logistic regression:

How to use C statistic and SPSS logistic regression?

C Statistic and SPSS Logistic Regression. C Statistic and SPSS Logistic Regression. I have used the SPSS LOGISTIC REGRESSION command (Analyze>Regression>Binary Logistic… in the menus). I would like to have the c statistic, as output by SAS PROC LOGISTIC, included in my output.

How is logistic regression used in the ROC curve?

LOGISTIC REGRESSION predicts the higher of the 2 values of the dependent variable (DV). If that DV was coded 0 and 1, LOGISTIC REGRESSION predicts the 1 value and 1 will be the ‘Value of state variable’ in the ROC curve dialog.

Where is the predicted probability stored in logistic regression?

By default, the predicted probability will be stored in a variable named pre_1 (the first time that you use the option in a session – then pre_2, pre_3, etc.). You can choose a different variable name if you run the LOGISTIC REGRESSION command from a syntax window.