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.

1224 questions
5
votes
2 answers

How to apply KNN on a mixed dataset(numerical + categorical) after doing one hot encoding using sklearn or pandas

I am trying to create a recommender based on various feature of an object(eg: categories,tags,author,title,views,shares,etc). As you can see these features are of mixed type and also I do not have any user-specific data. After displaying details of…
sns
  • 221
  • 4
  • 17
5
votes
1 answer

LabelBinarizer yields different result in multiclass example

When executing the multiclass example in the scikit-learn tutorial http://scikit-learn.org/stable/tutorial/basic/tutorial.html#multiclass-vs-multilabel-fitting I came across a slight oddity. >>> import sklearn >>> sklearn.__version__ 0.19.1 >>>…
miku
  • 181,842
  • 47
  • 306
  • 310
5
votes
3 answers

One-hot-encoding with missing categories

I have a dataset with a category column. In order to use linear regression, I 1-hot encode this column. My set has 10 columns, including the category column. After dropping that column and appending the 1-hot encoded matrix, I end up with 14…
lipsumar
  • 944
  • 8
  • 22
5
votes
2 answers

How to get one hot encoding of specific words in a text in Pandas?

Let's say I have a dataframe and list of words i.e toxic = ['bad','horrible','disguisting'] df = pd.DataFrame({'text':['You look horrible','You are good','you are bad and disguisting']}) main =…
Bharath M Shetty
  • 30,075
  • 6
  • 57
  • 108
5
votes
2 answers

Random Forest Regression for categorical inputs on PySpark

I have been trying to do a simple random forest regression model on PySpark. I have a decent experience of Machine Learning on R. However, to me, ML on Pyspark seems completely different - especially when it comes to the handling of categorical…
honeybadger
  • 1,465
  • 1
  • 19
  • 32
5
votes
1 answer

Pandas for Python: Exception: Data must be 1-dimensional

Here's what I got from a tutorial # Data Preprocessing # Importing the libraries import numpy as np import matplotlib.pyplot as plt import pandas as pd # Importing the dataset dataset = pd.read_csv('Data.csv') X = dataset.iloc[:, :-1].values y =…
Tyler L
  • 835
  • 2
  • 16
  • 28
5
votes
1 answer

Binary Crossentropy to penalize all components of one-hot vector

I understand that binary cross-entropy is the same as categorical cross-entropy in case of two classes. Further, it is clear for me what softmax is. Therefore, I see that categorical cross-entropy just penalizes the one component (probability) that…
5
votes
3 answers

sklearn mask for onehotencoder does not work

Considering data like: from sklearn.preprocessing import OneHotEncoder import numpy as np dt = 'object, i4, i4' d = np.array([('aaa', 1, 1), ('bbb', 2, 2)], dtype=dt) I want to exclude the text column using the OHE functionality. Why does the…
PascalVKooten
  • 20,643
  • 17
  • 103
  • 160
4
votes
5 answers

Split variable into multiple multiple factor variables

I have some dataset similar to this: df <- data.frame(n = seq(1:1000000), x = sample(LETTERS, 1000000, replace = T)) I'm looking for a guidance in finding a way to split variable x into multiple categorical variables with range 0-1 In the end it…
4
votes
1 answer

how to convert a csv file to character level one-hot-encode matrices?

I have a CSV file that looks like this I want to choose the last column and make character level one-hot-encode matrices of every sequence, I use this code and it doesn't work data = pd.read_csv('database.csv', usecols=[4]) alphabet = ['A', 'C',…
4
votes
1 answer

One-hot encode labels in keras

I have a set of integers from a label column in a CSV file - [1,2,4,3,5,2,..]. The number of classes is 5 ie range of 1 to 6. I want to one-hot encode them using the below code. y = df.iloc[:,10].values y = tf.keras.utils.to_categorical(y,…
emmasa
  • 177
  • 2
  • 7
4
votes
1 answer

Pandas group by one hot encoded columns

I have my Pandas data frame in the following way (basically one hot encoded columns): MovieID Action Adventure Animation Childrens Comedy Crime Documentary rating 1 0 0 1 1 1 0 0 …
Rulli
  • 105
  • 5
4
votes
1 answer

OneHotEncoding Protein Sequences

I have an original dataframe of sequences listed below and am trying to use one-hot encoding and then store these in a new dataframe, I am trying to do it with the following code but am not able to store because I get the following output…
4
votes
2 answers

One-Hot Encoding of label not needed?

I am trying to understand a code block from a guided tutorial for the classic Iris Classification problem. The code block for the final model is given as follows chosen_model = SVC(gamma='auto') chosen_model.fit(X_train,Y_train) predictions =…
4
votes
1 answer

Output column already exists error when fit with pipeline PySpark

I'm trying to create a pipeline in PySpark in order to prepare my data for Random Forest. I'm using Spark 2.2 (2.2.0.2.6.4.0-91). My data contains no null values. I identified the categorical columns and numerical columns. I'm encoding categorical…