Questions tagged [machine-learning]

Machine Learning is a subfield of computer science that draws on elements from algorithmic analysis, computational statistics, mathematics, optimization, etc. It is mainly concerned with the use of data to construct models that have high predictive/forecasting ability. Topics include modeling building, applications, theory, etc.

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3answers
7k views

Sentiment Analysis model for Spanish

I barely know about Data Analysis tools and techniques, so bare with me if I'm asking something too trivial. I'm looking for a Sentiment Analysis tool to process comments in Spanish. I do know some ...
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3answers
672 views

Data driven approach to define a churn user

I'm trying to define a churn prediction model for an online service (betting/gambling). A lot of papers talk about churn analysis/prediction for telco companies where defining a churn user is ...
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1answer
272 views

Sequence of numbers as single feature

Is it possible to use a sequence of numbers as one feature? For example, using libsvm data format: ...
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1answer
608 views

identifying input sequence using neural network

I fount simple neural scenario sayinh : network having 3 layers, 3 inputs and 2 outputs. It should be trained to recognize a simple pattern - if inputs are correspondingly 6.0,7.0 and 8.0 then outputs ...
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1answer
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Testing bimodality of data

I am trying to see if my data is multimodal (in fact, I am more interested in bimodality of the data). I performed dip test and it does evidence against unmodal data. However, I want to see, in ...
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0answers
3k views

Error::Type of predictors in new data do not match that of the training data

I am building a classification model using randomForest. When trying to predict I get the below error Type of predictors in new data do not match that of the ...
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4answers
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Custom trained model in Azure ML

I have a predictive model which I trained on a training set. I have written it in R. Now I want to deploy it as a web service so anyone can just input the data into it and get the output from the ...
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1answer
100 views

Adaptive learning of user's IoT setting preferences

We are working on a project to Predict the settings of the IoT devices(fan/light/AC) the user is using, based on his: location, outside temperature, humidity, time of the day etc... Training data is ...
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1answer
4k views

Item-Item similarity based on text

We're build an item-item recommender based on the text descriptions of the items. Our initial approach was to calculate the TF-IDF vectors for each item. We used a hashing tf with 5000 possible hashes ...
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2answers
354 views

Is our data “Big Data” (Startup)

I worked at a startup/medium sized company and I am concerned that we may be over-engineering one of our products. In essence, we will be consuming real-time coordinates from vehicles and users and ...
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1answer
2k views

Contributions of each feature in classification?

I have some features and I am using Weka to classify my instances. For example I have: Number of adj number of adverb number of punctuation in my feature ...
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74 views

Train a classifier for a game with feedback on chosen move instead of true labels

I'm having some trouble describing in one line what I want, which is probably why I haven't had much luck with Google. Say I have a game like 2048 where the possible actions each step are fixed (and ...
3
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1answer
121 views

semantic relation or semantic relatedness between terms or phrases

I am looking for a method that can realize if there is any semantic relation between two terms using ontologies. For example given two terms "kitchen" and "Chef" it can return s.th like chef works in ...
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3answers
289 views

What is a good non cryptographic Hash for string feature translation?

What would be a good non cryptographic Hash function to use for converting string features to a numerical representation for feeding into machine learning algorithms? To explain the scenario my ...
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7answers
80k views

Open source Anomaly Detection in Python

Problem Background: I am working on a project that involves log files similar to those found in the IT monitoring space (to my best understanding of IT space). These log files are time-series data, ...
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2answers
8k views

How to convert unstructured texts to structured data?

I would like to write an algorithm to convert unstructured texts (with contest descriptions) to structured data with the following fields: contest start date (optional) contest end date main prize ...
2
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2answers
1k views

Combining Datasets with Different Features

I have multiple datasets, with slightly differing features. What tools can I use to make this a homogeneous dataset? Dataset1: ...
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1answer
169 views

Markov Chains: How much steps to conclude a Transition Matrix

I have just learned Markov Chains which I am using to model a real world problem. The model comprises 3 states [a b c]. For now I am collection data and calculating ...
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2answers
276 views

How to extract information from plot images?

Are there any free tools or libraries that can understand a plot image file automatically? Things like type detection (line, bar, scatter), as well as label and axis scaling detection. In the tools I ...
0
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1answer
769 views

Finding Episodes in event sequence

In the paper "Discovery of frequent episodes in event sequences" by Mannila et al., a method for finding frequent episodes in an event sequence if a class of episodes and a sequence of events is given....
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2answers
121 views

Deriving Confidences from Distribution of Class Probabilities for a Prediction

I run into this problem from time to time and have always felt like there should be an obvious answer. I have probabilities for potential classes (from some classifier). I will offer the prediction ...
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2answers
232 views

Spam detection in social media

I want to train a binary classification algorithm for spam detection using labeled data set of mentions from social media. These mentions have the following features: URL, text message, posting ...
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2answers
3k views

What features from sound waves to use for an AI song composer?

I am planning on making an AI song composer that would take in a bunch of songs of one instrument, extract musical notes (like ABCDEFG) and certain features from the sound wave, preform machine ...
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0answers
205 views

Find correlation in observed data

I have a method that calculates a certain variable. This variable is biased by an error which should be related to the observables that were used to calculated the variable. I don't have an exact ...
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1answer
141 views

Learn and sample from a generative model with 2000 boolean features

My data is a set of about 1 million training examples, where each example is represented by about 2000 boolean features. Examples aren't labelled - it wouldn't really have any meaning in this domain. ...
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0answers
153 views

Problem while reusing model for new observations

I want to build a model using R, save it and reloading it when required. I am able to save the model and reload it without any problem, however when i use the model along with predict statement, I am ...
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0answers
394 views

Errror in confusionMatrix in R

While i am using the confusionMatrix in R, I am getting the following error: Error in binom.test(sum(diag(x)), sum(x)) : 'n' ...
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1answer
115 views

Machine learning for state-based transforms?

If I provide: A list of possible transforms, and, A list of input states, and, A corresponding list of output states for each input state, and, A fitness function to score each output state Which ...
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2answers
326 views

Cooperative Reinforcement Learning

I already have a functioning $Q(\lambda)$ implementation for a single agent working on a dynamic pricing problem with the goal of maximizing revenue. The problem that I'm working with, however, ...
5
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2answers
933 views

Can theano work on mapreduce or on spark?

I am not sure whether the Theano library can be used to write parallelized code in map reduce or in spark. Any expert opinion is welcome. A discussion was on at: Theano-dev
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2answers
470 views

Adjusting Probabilities When Using Alternative Cutoffs For Classification

I am reading Applied Predictive Modeling by Max Khun. I chapter 16 he discusses using alternate cutoffs as a remedy for class imbalance. Suppose our model predicts the most likely outcome of 2 events,...
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1answer
412 views

Scalable open source machine learning library written in python

I believe sci kit learn is written in python,however that not scalable.Spark mlib or ml is scalabale but written in scala.I am looking for an ongoing effort where a machine learning library is being ...
2
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1answer
108 views

Temporal Difference Learning Getting Stuck

I'm trying to implement a temporal difference algorithm that learns the maximum revenue over a period of time using prices as the actions, inventory as the state, and revenues realized as the reward. ...
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1answer
7k views

R - Interpreting neural networks plot

I know there are similar question on stats.SE, but I didn't find one that fulfills my request; please, before mark the question as a duplicate, ping me in the comment. I run a neural network based on ...
2
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2answers
4k views

What is the actual output of Principal Component Analysis?

I'm trying to understand PCA, but I don't have a machine learning background. I come from software engineering, but the literature I've tried to read so far is hard for me to digest. As far as I ...
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4answers
26k views

How to avoid overfitting in random forest?

I want to avoid overfitting in random forest. In this regard, I intend to use mtry, nodesize, and maxnodes etc. Could you please help me choose values for these parameters? I am using R. Also, if ...
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0answers
47 views

Trying to come up with a feature to improve emotion classifier based on facial movement using facial landmarks

I managed to create an emotion recognition system that uses dense optical flow on each entire frame. While the accuracy range is within 80-90% with cross-validation, I am aiming to improve the ...
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1answer
50 views

Similar Candidate Recommendations

I've just embarked on a project to recommend similar candidates to employers for a website that offers employers the ability to search its CV database. My background is in engineering research on ...
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4answers
172 views

Definition of “inside” in K-means?

After conducting a cluster analysis using K-means, I have new data coming online that I need to detect anomalies with. Anomalies are assumed to not be within the clusters. So, how is one to define "...
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2answers
353 views

What should I care about while stacking as an ensemble method?

I'm using SMO, Logistic Regression, Bayesian Network and Simple CART algorithms for classification. Results form WEKA: ...
5
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2answers
790 views

How are clusters from DBSCAN sometimes non-convex?

I've been using clustering in my bag of ML techniques for quite some time now, and I've never found a satisfying answer to this question. In DBSCAN, we define a maximum radius with which to form ...
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1answer
4k views

What are the performance measures in the neural networks field?

I constructed a neural networks in R using neuralnet package. I want to test that using cross-validation, that is a technique based on using 4/5 of the dataset to ...
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1answer
65 views

Questions for data analysis of a class room

I have Wireless Sensor Network setup in a classroom. I'm sensing data like temp, humidity, light, occupancy, etc. Classroom can accommodate 150 students and has 6 AC with light. From one side the ...
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7answers
3k views

Data science projects explained step by step?

I am looking for a website or book where several practical examples are given step by step, explaining how they choose the relevant features, the model selection procedure, etc...
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1answer
912 views

Cross validation for C5.0 algorithm

I want to try K-fold cross validation in R for C5.0 algorithm, The following is the code i use. Can someone suggest me how can i include k-fold as well? Classifi_C5.0 <- C5.0(TARGET ~., , data = ...
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0answers
86 views

How to include class as a feature

I am currently experimenting with the idea of including the class of a feature vector as a separate feature. My work is about preposition selection in learner language use. I want to train a ...
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2answers
576 views

How to speed up optimization using Differential Evolution?

My application is high frequency trading. My data are time series of the bid and ask prices of a stock recorded on every tick (change in price). For each data point I also have a certain indicators ...
2
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1answer
165 views

Predict set elements based on other elements

Sorry if this has been answered before but could someone help me with solving the following problem: Each symbol in a dataset has a set of labels. Given a set of labels how can we predict more labels ...
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3answers
3k views

Root Mean Squared Error (RMSE) - significance of square root

What is the significance of the square root in root-mean-square-error? Essentially, my question is: what is the difference between (rms error) and (rms error)$^2$?
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2answers
155 views

Data repositories like UCI

Are there any other data repositories like UCI and mlData, for biological data?? I want to know about mostly biological data set.

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