How do you do 1-vs-rest classifiers in XGBoost Library (Not Sklearn)?

I am working with a very large dataset that would benefit from using training continuation with the xgb_model parameter in xgb.train(). The label (Y) of dataset itself has 4 classes and is highly imbalanced, so I would like to generate per-label PR curves for it to evaluate its performance, and would thus need to treat each class as it's own binary problem using a one-vs-rest classifier. After a lot of reading I haven't found an equivalent to sklearn's OneVsRestClassifier in …
Category: Data Science

Co-joining multi-peak histograms

I am analysing a bunch of data files which represent responsiveness of cells to addition of a drug. If a drug is not added, cell responds normally, if it is added, it shows abnormal patterns: , . We decided to analyse this using an amplitude histogram, in order to distinguish between a change in amplitude and in change of a probability of elliciting the binary response. What we get with file 1 is : So we fit a pdf on …
Category: Data Science

Basic Machine Learning Question, Looking at where to start

Was recommended to post here instead of StackOverflow I am looking to do some ML, and I just need to know the words to start going off and which library/path to go down. I have two data sets that look something like the below, | UserName | Location | Department | |test.user | Chicago | IT | |asd.smith | LA | Marketing | |qwe.smith | Chicago | IT | |dfg.smith | Chicago | Marketing | and | UserName | Permission …
Category: Data Science

How to train LGBMClassifier using optuna

I am trying to use lgbm with optuna for a classification task. Here is my model. from optuna.integration import LightGBMPruningCallback import optuna.integration.lightgbm as lgbm import optuna def objective(trial, X_train, y_train, X_test, y_test): param_grid = { # "device_type": trial.suggest_categorical("device_type", ['gpu']), "n_estimators": trial.suggest_categorical("n_estimators", [10000]), "learning_rate": trial.suggest_float("learning_rate", 0.01, 0.3, log=True), "num_leaves": trial.suggest_int("num_leaves", 20, 3000, step=20), "max_depth": trial.suggest_int("max_depth", 3, 12), "min_data_in_leaf": trial.suggest_int("min_data_in_leaf", 100, 10000, step=1000), "lambda_l1": trial.suggest_int("lambda_l1", 0, 100, step=5), "min_gain_to_split": trial.suggest_float("min_gain_to_split", 0, 15), "bagging_fraction": trial.suggest_float( "bagging_fraction", 0.2, 0.95, step=0.1 ), "bagging_freq": trial.suggest_categorical("bagging_freq", [1]), …
Category: Data Science

Evaluate a model based on precision for multi class classification

I have a model that predicts the level of injury over 3 classes: Low, Medium and High. I wish to optimize the model parameters on the scoring basis of precision. However, precision is class specific, we can determine the precision of low, medium and high separately. Is there a way to determine something like "Overall Precision" from the confusion matrix?
Category: Data Science

Text2Slide multiclass classification

I am considering an idea of stitching together a slide deck based on text input, e.g. given: An all-hands presentation with business updates, project timelines, and financial report charts the output could be a deck with slides corresponding to Title, List, Calendar, Pie Chart, Conclusion. I have preexisting slides that are mostly categorized by the "form" ranging from very general like List to more specific like Decision Tree or Venn Diagram. Am I on the right track that this sounds …
Category: Data Science

Identify optimal thresholds for one-vs-one/one-vs-rest ROC-curve for multiclass classification

Say I have a multiclass classification problem with N classes. I have trained a classifier on a training set, I use a validation set and a One-vs-rest ROC-curve to give me N ROC curves. Since the ROC curve is created based on different thresholds of when we classify a sample as $Ci$ or not $Ci$. We can then chose (our) optimal FPR/TRP ratio and get the threshold (t) e.g say t=0.6 we classify a sample as $Ci$ if model_score>=0.6 else …
Category: Data Science

How to compute f1_score for multiclass multilabel classification

I have used one hot encoder [1,0,0][0,1,0][0,0,1] for my functional classification model. The predicted probabilities for test data yprob = model.predict(testX) gives me : yprob = array([[0.18120882, 0.5803128 , 0.22847839], [0.0101245 , 0.12861261, 0.9612609 ], [0.16332535, 0.4925239 , 0.35415074], ..., [0.9931931 , 0.09328955, 0.01351734], [0.48841736, 0.25034943, 0.16123319], [0.3807928, 0.42698202, 0.27493873]], dtype=float32) I would like to compute the Accuracy, F1 score and the confusion matrix from this. The sequential api offers a predict_classes function to do it. yclasses = model.predict_classes(testX) and …
Category: Data Science

AUC-ROC for Multi-Label Classification

Hey guys I'm currently reading about AUC-ROC and I have understood the binary case and I think that I understand the multi-classification case. Now I'm a bit confused on how to generalize it to the multi-label case, and I can't find any intuitive explanatory texts on the matter. I want to clarify if my intuition is correct with an example, let's assume that we have some scenario with three classes (c1, c2, c3). Let's start with multi-classification: When we're considering …
Category: Data Science

How to add class labels to confusion matrix of multi class classification

How do I add class labels to the confusion matrix? The label display number in the label not the actual value of the label Eg. labels = ['A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'] Here is the code I used to generate it. x_train, y_train, x_test, y_test = train_images, train_labels, test_images, test_labels model = KNeighborsClassifier(n_neighbors=7, metric='euclidean') model.fit(x_train, y_train) # predict labels for test data predictions = model.predict(x_test) # Print overall accuracy print("KNN Accuracy = ", metrics.accuracy_score(y_test, predictions)) # Print confusion matrix cm = confusion_matrix(y_test, predictions) plt.subplots(figsize=(30, …
Category: Data Science

Text similarity for badly written text

Consider the following scenario: Suppose two lists of words $L_{1}$ and $L_{2}$ are given. $L_{1}$ contains just bad-written phrases (like 'age' instead of '4ge' or 'blwe' instead of 'blue' etc.). On the other hand, each element of $L_{2}$ is a well-written version of each element of $L_{1}$. Here is an example: $$L_{1}=[...,dqta \ 5ciencc,...,s7ack \ exch9nge,...],$$ $$L_{2}=[...,stack \ exchange,...,data \ science,...].$$ Problem: Is there any strategy to try to predict which element $w^{\prime}$ in $L_{2}$ is the syntactically correct counterpart …
Category: Data Science

Reduce multiclass classification targets to binary classification targets in scikit-learn

I would like to reduce multiclass classification targets to binary classification targets. Ideally, this mapping would happen within scikit-learn so the same transformation applies during both training and prediction. I looked at transforming the prediction target (y) documentation but did not see something that would work. Ideally, it would be a classifier version of TransformedTargetRegressor. Something like this mapping: targets_multi = {'A', 'B', 'C', 'D'} targets_binary = {0: {'A', 'B'}, 1: {'C', 'D'}}
Category: Data Science

Using Sci-Kit Learn Clustering and/or Random-Forest Classification on String Data with Multiple Sub-Classifications

I have a set of data with some numerical features and some string data. The string data is essentially a set of classes that are not inherently related. For example: Sample_1,0.4,1.2,kitchen;living_room;bathroom Sample_2,0.8,1.0,bedroom;living_room Sample_3,0.5,0.9,None I want to implement a classification method with these string-subclasses as a feature; however, I don't want to have them be numerically related or have the comparisons be directly based on the string itself. Additionally, if samples have no data in this column they should not be …
Category: Data Science

Multi-Label time-series classification with LSTM: large performance decrease for longer periods

I have daily data on event occurences, so for each day I have a vector like [1, 0, 1] indicating that on this day event one and three occured, but event two did not occur. I want to train a model to take data from the past number of days (n_days) and to then predict the event occurences for the next day. I believe this problems falls into the category of multi-label classification. Moreover, the data that I use has …
Category: Data Science

'list' object has no attribute 'lower' TfidfVectorizer

I have a dataframe with two text columns and I converted them to a list. I seperated the train and test data as well. But while making a base model TfidfVectorizer throws me an error of 'list' object has no attribute 'lower' Here is the code X['ItemDescription']= X['ItemDescription'].str.lower() X['DiagnosisOne'] = X['DiagnosisOne'].str.lower() from sklearn.model_selection import train_test_split X_train,X_test, y_train, y_test = train_test_split(X,y,test_size=0.2, random_state=42) # Convert abstract text lines into lists train_items = X_train.reset_index().values.tolist() test_items = X_test.reset_index().values.tolist() from sklearn.preprocessing import LabelEncoder label_encoder = …
Category: Data Science

Binary classification from local and global feature selection

I want to train a deep leaning model, consisting of images. My question is which scenariowas chosen to train the model? scenario 1 : I train images local context on Output 1, and I train images clobal contet on Output 2, Finally, combine these two outputs to get a binary classification. scenario 2 : Train global and local context directly on the binary classification. This is what I mean by local and global context (This is just an example):
Category: Data Science

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