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Algorithm
Leetcode style algorithm
Natural Language Processing
Scraping Reviews
AirBNB
Amazon
Google
Microsoft
Microsoft: Time Series Analysis of Cons Reviews
Review Comparison
Exploratory Data Analysis
2017 H1B Visa Data: Overview
HR Analytics: Why Do Employees Leave?
Hospital Analytics: US Best Hospitals
IRS Data: Washington State Migration
Real Estate: Discovering Buyer Preferences
San Francisco Crime: The Least Family-Friendly District
Interactive Visualization
Hospital Analytics Interactive Visualization
H1B Data – Salary
Practical Machine Learning
HR Analytics: Who Is Next?
House Prices: How Much Should the Prices Be?
Machine Learning
Anova and Model Comparison
Fitting Classical Decision Tree
Fitting Conditional Inference Tree
Fitting kNN
Fitting Lasso Regression
Fitting Non-Linear Model: Polynomial
Fitting Principal Component Analysis
Fitting Ridge Regression
Fitting Support Vector Machine – Classification
Fitting Support Vector Machine – Regression
Cross-Validation: Random Selection
Cross-Validation: LOOCV
Cross-Validation: k-Folds
Gradient Descent
Model Selection: Best Subset Selection
Model Selection: Forward, Backward Selection
Multiple Regression Calculation
Polynomial
Stats: Covariance and Correlation
Stats: Mean, Variance, and Standard Deviation
Data Wrangling
& or &&
Adding a Cumulative Sum Column
Adding Leading and Trailing Character/Whitespace
Changing Column Names
Counting All Categorical Variables
Creating New Variables with ifelse()
Extracting Only Even/Odd Rows/Columns
Locating NAs
Missing Value Imputation
Removing Rows with NAs
Removing Leading/Trailing Whitespace
Removing Punctuation and Symbols
Reordering Columns
Reordering Factor Variables
Reshaping Long to Wide Format
Reshaping Wide to Long Format
Selecting Columns
source() function
Subtracting Value from a Previous Row
Text Counting
Using for loop with str_replace_all
Vlookup in R
Python = R
Cheat Sheet
Clearing Workspace
Head & Tail
Load CSV Files
Working with Directory
Adding Latest R Version to Jupyter Notebook
SQL
Common Table Expression
CREATE, INSERT, UPDATE, DELETE, and DROP
DISTINCT
EOMONTH
LAG and LEAD
LEFT and RIGHT
PARSENAME and REPLACE
RANK and DENSE_RANK
SELECT INTO
UNION and SORT BY
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