Class Weights for Handling Imbalanced Datasets

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  • เผยแพร่เมื่อ 27 ต.ค. 2024

ความคิดเห็น • 47

  • @bhattbhavesh91
    @bhattbhavesh91  5 ปีที่แล้ว +10

    Something went wrong while using pd.crosstab! So the updated confusion matrices are as follows -
    At 2:06
    The correct confusion matrix is
    93800 78
    38 71
    At 5:19
    The correct confusion matrix is
    91548 13
    2290 136
    At 8:30
    The correct confusion matrix is
    93791 30
    47 119
    Sorry for the mistake :)

    • @ruuiipinge9680
      @ruuiipinge9680 4 ปีที่แล้ว

      Dont you have the previous video you referred to?

    • @lavanshuagrawal8367
      @lavanshuagrawal8367 4 ปีที่แล้ว

      Hi, Thanks for the amazing video. I have 2 questions:
      First question is similar to other posts. Why the weights are chosen to be 'x' and '1-x'?
      Second is about the working of GridSearchCV. I think the it searches across the 20 intervals from 0.05 to 0.95. Then, how the optimum value of x for 0 was found to be 0.097 and not 0.1? (And similarly 0.902 for 1 and not 0.9?)

    • @ganeshkharad
      @ganeshkharad 3 ปีที่แล้ว

      yes you should have used sklearn confusion matrix method

    • @yaroslavprysiazhnyi5979
      @yaroslavprysiazhnyi5979 2 ปีที่แล้ว

      Hello , could you tell me why I have ValueError: Invalid parameter ratio for estimator SMOTE(). Check the list of available parameters with `estimator.get_params().keys()`. for row 51

  • @amanjangid6375
    @amanjangid6375 4 ปีที่แล้ว +4

    True Positive is 0, it means model incorrectly classifies all the frauds (class=1), but we want to more focus on true positive as in case of credit fraud detection. Why this is happening

  • @rahuldey6369
    @rahuldey6369 3 ปีที่แล้ว +1

    I have checked your videos regarding handling imbalanced datasets. Just wanted to know, what is the recommended technique to use for such cases -
    1. If use undersampling then there's a potential chance of losing huge data
    2. If I use class_weights, it gives me a reasonable f1
    3. If I use SMOTE, it also gives me a good performance. But I believe there might lie a probability that the synthetic data points might look like the test cases, which is indirect data leakage
    What do you recommend and why?

  • @dragscorpio900
    @dragscorpio900 4 ปีที่แล้ว +3

    hi, could you explain How to use class weight when we have multiclass? Like.. how do we get to know best parameters of classs_weight after hyperparameter tuning??

  • @poojyathavenkatesh2980
    @poojyathavenkatesh2980 ปีที่แล้ว

    Thank you so much

  • @bishnumurmu8286
    @bishnumurmu8286 5 ปีที่แล้ว +5

    Hi Bhavesh, how can we do grid search for multi-class. As you have set 2 class weights to x and 1-x. How to set it for 4 classes.

    • @rahuldey6369
      @rahuldey6369 3 ปีที่แล้ว +1

      Yeah, that's I was also wondering

  • @ashishraj5882
    @ashishraj5882 4 ปีที่แล้ว +1

    hi, why to use ROC curve ?? precision recall has to be used for imbalanced data set isn't it ???

  • @pavitrag201
    @pavitrag201 3 ปีที่แล้ว

    Hi, Thanks for the detailed explanation, i am not able to access your notebook

  • @AG-dt7we
    @AG-dt7we 2 ปีที่แล้ว

    Thanks, nice video..
    What do you recomend more...down sampling or using class_weights ?

  • @soumyaranjansethi1790
    @soumyaranjansethi1790 4 ปีที่แล้ว

    Amazing sir👌👌

  • @maryamzeinolabedini1515
    @maryamzeinolabedini1515 2 ปีที่แล้ว

    Hi, thanks for teaching. I have a question. How can we use class weight for bayesian network?

  • @21Gannu
    @21Gannu 3 ปีที่แล้ว

    Bhavesh you mentioned clearly this class weights penalizes the false negative what if you want to penalise the false positive rate??

  • @hananeouach976
    @hananeouach976 4 ปีที่แล้ว

    Thank you soo much this is really interesting and it was really helpful for my project

    • @bhattbhavesh91
      @bhattbhavesh91  4 ปีที่แล้ว

      Glad it was helpful!

    • @niyazahmad9133
      @niyazahmad9133 4 ปีที่แล้ว

      @@bhattbhavesh91 come on replying only for girls ha ha...!

    • @afeezlawal5167
      @afeezlawal5167 2 ปีที่แล้ว

      @@bhattbhavesh91 hello prof.
      With the f_score of 77% , is it okay to deploy this particular model into production?

  • @dragscorpio900
    @dragscorpio900 4 ปีที่แล้ว

    hi, when you use cv for optimal weight, why does the weight need to be "x" and "1-x" ? The "balanced" option produces weights that do not sum up to become 1. so why do we use gridsearch to find weights in the range [0,1] ?

  • @gardeninglessons3949
    @gardeninglessons3949 3 ปีที่แล้ว

    very helpful thankyou

  • @taylorw2384
    @taylorw2384 5 ปีที่แล้ว

    This was helpful. Thanks

  • @jozelazarevski1
    @jozelazarevski1 5 ปีที่แล้ว +1

    Very insightful! I will try this soon and come back with feedback! :) Have a nice day and thank you for your efforts!

  • @tirthadatta7368
    @tirthadatta7368 2 ปีที่แล้ว +1

    Sir, Can we use 'class_weight = balanced' for multiclass classification and deep learning also??

    • @nisargbarot1998
      @nisargbarot1998 ปีที่แล้ว

      Bro did you get to know, how to perform it for multiclass?

  • @paymankhayree8552
    @paymankhayree8552 4 ปีที่แล้ว

    nice explanations

  • @atilaabdula1642
    @atilaabdula1642 4 ปีที่แล้ว

    What if we have a multilabel or even multioutput task? In my experience class_weights don t work in those cases. Pls correct me if I am wrong

  • @abhijeetrathore6072
    @abhijeetrathore6072 5 ปีที่แล้ว +1

    Hi bhavesh
    Where can i find the dataset and Jupiter notebook

    • @bhattbhavesh91
      @bhattbhavesh91  5 ปีที่แล้ว

      github.com/bhattbhavesh91/imbalance_class_sklearn

    • @chrisxu5158
      @chrisxu5158 4 ปีที่แล้ว

      @@bhattbhavesh91 thanks

  • @karndeepsingh
    @karndeepsingh 5 ปีที่แล้ว

    What is the difference between SMOTE and Class_weight?? When to use SMOTE and Class_weight?

    • @saswatapaladhi4608
      @saswatapaladhi4608 ปีที่แล้ว

      as far as i know smote is used to create artificial dataset for minority class. But problem will be for say an image dataset where it will be inaccurate to generate images for minority classes so for that u would need this class_weight method

  • @karndeepsingh
    @karndeepsingh 5 ปีที่แล้ว

    How to use class weight when we have multiclass? Like.. how do we get know best parameters of classs_weight after hyperparameter tunining??

  • @dhananjaykansal8097
    @dhananjaykansal8097 5 ปีที่แล้ว

    Niceeeeeeeeee

  • @soumyadrip
    @soumyadrip 3 ปีที่แล้ว

    1:12 it will be logistic regression

  • @michaelscheinfeild9768
    @michaelscheinfeild9768 ปีที่แล้ว

    true positive is 0 ! so f1 is almost 0 your table has some mistake

  • @selva279
    @selva279 5 ปีที่แล้ว

    Hi can this applied to KNN?

  • @inferno9004
    @inferno9004 5 ปีที่แล้ว

    hi, when you use cv for optimal weight, why does the weight need to be "x" and "1-x" ? The "balanced" option produces weights that do not sum up to become 1. so why do we use gridsearch to find weights in the range [0,1] ?