# C penalty in SVM - larger C increases the margin or reduces the margin?

I get contradictory information on what the penalty value C does in SVM.

page 346,347 of the following book says, larger C means larger misclassification is allowed and margin will be larger. http://faculty.marshall.usc.edu/gareth-james/ISL/ISLR%20Seventh%20Printing.pdf

same says the below link (in regularization section) https://www.datacamp.com/community/tutorials/svm-classification-scikit-learn-python

However, every other source I read says C in svm class of python stands for penalty and larger C means higher penalty and thereby lower margin. (But going by the above book and the optimization equations, C is the allowance for misclassification and this seems correct - based on the formula).

• I think the first one is wrong. Larger cost means that misclassification is penalized more, which should imply a lower margin. – George Jul 31 '19 at 19:22