Questions tagged [one-hot-encoding]

One-Hot Encoding is a method to encode categorical variables to numerical data that Machine Learning algorithms can deal with. One-Hot encoding is most used during feature engineering for a ML Model. It converts categorical values into a new categorical column and assign a binary value of 1 or 0 to those columns.

Also known as Dummy Encoding, One-Hot Encoding is a method to encode categorical variables, where no such ordinal relationship exists, to numerical data that Machine Learning algorithms can deal with. One hot encoding is the most widespread approach, and it works very well unless your categorical variable takes on a large number of unique values. One hot encoding creates new, binary columns, indicating the presence of each possible value from the original data. These columns store ones and zeros for each row, indicating the categorical value of that row.

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How to use the output from OneHotEncoder in sklearn?

I have a Pandas Dataframe with 2 categorical variables, and ID variable and a target variable (for classification). I managed to convert the categorical values with OneHotEncoder. This results in a sparse matrix. ohe = OneHotEncoder() # First I…
Bert Carremans
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Scikit-Learn - one-hot encoding certain columns of a pandas dataframe

I have a dataframe X with integer, float and string columns. I'd like to one-hot encode every column that is of "Object" type, so I'm trying to do this: encoding_needed = X.select_dtypes(include='object').columns ohe =…
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pyspark - Convert sparse vector obtained after one hot encoding into columns

I am using apache Spark ML lib to handle categorical features using one hot encoding. After writing the below code I am getting a vector c_idx_vec as output of one hot encoding. I do understand how to interpret this output vector but I am unable to…
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Combine 2 dataframe and then separate them

I have 2 dataframes with same column headers. I wish to perform hot encoding on both of them. I cannot perform them one by one. I wish to append two dataframe together and then perform hot encoding and then split them into 2 dataframes with headers…
Mervyn Lee
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Do I need to use one_hot encoding if my output variable is binary?

I am developing a Tensorflow network based on their MNIST for beginners template. Basically, I am trying to implement a simple logistic regression in which 10 continuous variables predict a binary outcome, so my inputs are 10 values between 0 and 1,…
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Pyspark Dataframe One-Hot Encoding

I am doing data preparation on the Spark DataFrame with categorical data. I need to do One-Hot-Encoding on the categorical data and I tried this on spark 1.6 sqlContext = SQLContext(sc) df = sqlContext.createDataFrame([ (0, "a"), (1, "b"), …
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Logistic regression on One-hot encoding

I have a Dataframe (data) for which the head looks like the following: status datetime country amount city 601766 received 1.453916e+09 France 4.5 Paris 669244 received 1.454109e+09 Italy 6.9 …
Mornor
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How to handle unseen categorical values in test data set using python?

Suppose I have location feature. In train data set its unique values are 'NewYork', 'Chicago'. But in test set it has 'NewYork', 'Chicago', 'London'. So while creating one hot encoding how to ignore 'London'? In other words, How not to encode the…
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Ordinal Encoding or One-Hot-Encoding

IF we are not sure about the nature of categorical features like whether they are nominal or ordinal, which encoding should we use? Ordinal-Encoding or One-Hot-Encoding? Is there a clearly defined rule on this topic? I see a lot of people using…
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How to get original value for binary encoding using category_encoder package

I have a dataset which includes over 100 countries in it. I want to include these in an XGBoost model to make a classification prediction. I know that One Hot Encoding is the go-to process for this, but I would rather do something that wont increase…
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How to handle One-Hot Encoding in production environment when number of features in Training and Test are different?

While doing certain experiments, we usually train on 70% and test on 33%. But, what happens when your model is in production? The following may occur: Training Set: ----------------------- | Ser |Type Of Car | ----------------------- | 1 |…
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How do you One Hot Encode columns with a list of strings as values?

I'm basically trying to one hot encode a column with values like this: tickers 1 [DIS] 2 [AAPL,AMZN,BABA,BAY] 3 [MCDO,PEP] 4 [ABT,ADBE,AMGN,CVS] 5 [ABT,CVS,DIS,ECL,EMR,FAST,GE,GOOGL] ... First I got all the set of all the tickers(which is about…
Castle
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How to give column names after one hot encoding with sklearn?

Here is my question, I hope someone can help me to figure it out.. To explain, there are more than 10 categorical columns in my data set and each of them has 200-300 categories. I want to convert them into binary values. For that I used first label…
dss
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Getting correct shape for datapoint to predict with a Regression model after using One-Hot-Encoding in training

I am writing an application which uses Linear Regression. In my case sklearn.linear_model.Ridge. I have trouble bringing my datapoint I like to predict in the correct shape for Ridge. I briefly describe my two applications and how the problem turns…
moobi
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Pandas One hot encoding: Bundling together less frequent categories

I'm doing one hot encoding over a categorical column which has some 18 different kind of values. I want to create new columns for only those values, which appear more than some threshold (let's say 1%), and create another column named other values…
anwartheravian
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