Imbalance ratio formula in data mining

1. How do you calculate imbalance ratio?
2. What is the ratio for imbalanced dataset?
3. What is an unbalanced ratio?

How do you calculate imbalance ratio?

The imbalance ratio (IR) is the most commonly used measure to describe the imbalance extent of a dataset. IR is defined as(1) IR = N maj N min , where N_maj is the sample size of the majority class and N_min is the sample size of the minority class.

What is the ratio for imbalanced dataset?

The level of class imbalance of a dataset is given by the imbalance ratio (IR), so that an IR of 1:10 expresses that for each sample of the positive class there are 10 samples of the negative class.

What is an unbalanced ratio?

1. Is the proportion of the number of instances in the negative class to the number of instances in the positive one. Learn more in: Ensemble Learning via Extreme Learning Machines for Imbalanced Data. Find more terms and definitions using our Dictionary Search.