classification

问题 I'm applying a text classification in Weka using NaiveBayesMultinomialText classifier. The problem is that when I use the GUI to do it and test on the same train data (without cross validation) I get 93% acurracy, and when I try do it via java code I get 67% acurracy. What might be wrong? In GUI, I'm using the following configuration: Lnorm 2.0 debug False lowercaseTokens True minWordFrequency 3.0 norm 1.0 normalizeDocLength False periodicPruning 0 stemmer NullStemmer stopwords pt-br

问题 I have 30 ,40 pictures of humans , Which I want to get in Python code . And make group of similar pics . Like 5 pic of john and 10 of peter . like this . I am new in Image processing thing. So my question is which algo is best for this . And I want to do this on AWS lambda function . Any help would be highly appreciated. P.S (Its my first ever task in this field. Kindly ignore mistakes of tell me to improve them Thanks) 回答1: I would suggest you to do the thing with AWS Rekognition. It's

问题 I'm just wondering if this is a legitimate way of calculating classification accuracy: obtain precision recall thresholds for each threshold binarize the continuous y_scores calculate their accuracy from the contingency table (confusion matrix) return the average accuracy for the thresholds recall, precision, thresholds = precision_recall_curve(np.array(np_y_true), np.array(np_y_scores)) accuracy = 0 for threshold in thresholds: contingency_table = confusion_matrix(np_y_true, binarize(np_y

问题 I have gold data where I annotated all room numbers from several documents. I want to use openNLP to train a model that uses this data and classify room numbers. I am stuck on where to start. I read openNLP maxent documentation, looked at examples in opennlp.tools and now looking at opennlp.tools.ml.maxent - it seems like it is something what I should be using, but still I have no idea on how to use. Can somebody give me some basic idea on how to use openNLP maxent and where to start with?

问题 How do I visualize the SVM classification once I perform SVM training in Matlab? So far, I have only trained the SVM with: % Labels are -1 or 1 groundTruth = Ytrain; d = xtrain; model = svmtrain(groundTruth, d); 回答1: If you are using LIBSVM, you can plot classification results: % Labels are -1 or 1 groundTruth = Ytrain; d = xtrain; figure % plot training data hold on; pos = find(groundTruth==1); scatter(d(pos,1), d(pos,2), 'r') pos = find(groundTruth==-1); scatter(d(pos,1), d(pos,2), 'b') %

问题 I am using LogisticRegression from the sklearn package, and have a quick question about classification. I built a ROC curve for my classifier, and it turns out that the optimal threshold for my training data is around 0.25. I'm assuming that the default threshold when creating predictions is 0.5. How can I change this default setting to find out what the accuracy is in my model when doing a 10-fold cross-validation? Basically, I want my model to predict a '1' for anyone greater than 0.25, not

问题 I am working on a text classification problem, I am trying to classify a collection of words into category, yes there are plenty of libraries available for classification, so please dont answer if you are suggesting to use them. Let me explain what I want to implement. ( take for example ) List of Words: java programming language c-sharp List of Categories. java c-sharp here we will train the set, as: java maps to category 1. java programming maps to category 1.java programming maps to

问题 Most examples of neural networks for classification tasks I've seen use the a softmax layer as output activation function. Normally, the other hidden units use a sigmoid, tanh, or ReLu function as activation function. Using the softmax function here would - as far as I know - work out mathematically too. What are the theoretical justifications for not using the softmax function as hidden layer activation functions? Are there any publications about this, something to quote? 回答1: I haven't

问题 I Have an object with a set of parameters like: var obj = new {Param1 = 100; Param2 = 212; Param3 = 311; param4 = 11; Param5 = 290;} On the other side i have a list of object: var obj1 = new {Param1 = 1221 ; Param2 = 212 ; Param3 = 311 ; param4 = 11 ; Param5 = 290 ; } var obj3 = new {Param1 = 35 ; Param2 = 11 ; Param3 = 319 ; param4 = 211 ; Param5 = 790 ; } var obj4 = new {Param1 = 126 ; Param2 = 218 ; Param3 = 2 ; param4 = 6 ; Param5 = 190 ; } var obj5 = new {Param1 = 213 ; Param2 = 121 ;

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . Do you know of any good c++ svm libraries out there I tried libsvm http://www.csie.ntu.edu.tw/~cjlin/libsvm/ but so far I'm not