I'm working on a data set and wanted to know is there a standard rate about Class Imbalance problem or not?
I have 47 samples in Class A and 150 Sample in class B , should I use Class Imbalance Technique or these rates are normal?
There is no general rule but you better to use such techniques (SMOTE, sampling etc) and try to obtain 50:50 if you can. You can utilize my another answer (just ignore multiclass part).
My suggestion is you should create more samples by synthetic data generators like SMOTE. You have a model with very less observations (197). The model may not fit well thus data generation may help your for that case.
Hope it helps!