Archives: 2021/6 | DataScienceTribe

2021

06

23

rare event encoding for categorical feature in machine learning in pandas dataframe

If categorical features has too many values, it will generate too many features after encoding, such as one-hot encoding

2021-06-23 data science

18

handles feature order in training and online production stage to avoid inconsistent error

In applying machine learning models in production stage, like lightGBM model or any models.While we all know the order o

2021-06-18 data science

preprocessing pandas tip machine learning

15

some handy functions to group continous variables and missing value imputation in dataframe

Following example shows how to group age variable into groups,and some simple missing value imputaiton proecdures. There

2021-06-15 data science

python preprocessing pandas tip

14

explode and expand rows to multiple rows or columns to multiple columns using pandas dataframe

import pandas as pd generate some example some datadata = [ [['python','C'],'John'],[[&#x

2021-06-14 data science

python preprocessing pandas tip

12

aggregate features from different rows into one row in pandas dataframe

In many use cases, different features of the same event are stored in a table by multiple rows.multiple columns will ind

2021-06-12 data science

preprocessing pipeline feature engineering

10

time series feature engineering using tsfresh, training vs test

During the test stage, i.e., once the model is on production, for any new data,tsfresh feature generation does not depen

2021-06-10 data science

preprocessing pipeline feature engineering tsfresh time series

09

word tokenization and sentence tokenization in python using NLTK package

What is Tokenization?Tokenization is the process by which a large quantity of text is divided into smaller parts called

2021-06-09 data science

tokenization NLTK

08

missing value or null value processing in pandas dataframe

obtain null or missing values of a dataframeSuppose the dataframe has the following formats, with 10 rows and 5 clomns:

2021-06-08 data science

pandas dataframe

05

boost exact phrase search results ranking in elasticsearch

Elasticsearch use the DSL format to create query. One easy search is to use multi_match by passing the query key word, a

2021-06-05 search

python elasticsearch

04

how to convert timestamp column of pandas dataframe into hour and day features using transformer

from sklearn.base import BaseEstimator, TransformerMixinimport pandas as pdclass dayandhour_Transformer(BaseEstimator, T

2021-06-04 data science

python pandas preprocessing