===Feature Engineering==[[Feature engineering]] in machine learning is the transformation of raw data into features that better reflect the underlying problem to the predictive model. This results in improved model accuracy using unseen data. Using statistical analysis and domain knowledge, feature engineering identifies the relevant features that capture the underlying patterns of the data. This involves transforming and selecting the variables, creating new variables by combining or aggregating existing variable, and handling missing or incomplete information. ==Examples of Feature Engineering==Here are some examples of feature engineering:- [[One hot encoding]] of categorical variable to convert them into numerical variables- [[Standardization]] numerical variables to ensure that they have a common scale- [[Feature Scaling]] to handle variables that have different units of measurement- [[Binning]] of numerical variable to convert them into categorical variables- [[Polynomial Features]] to capture nonlinear relationships between variables- [[Feature Selection]] to remove redundant or irrelevant features ==Why Feature Engineering is Important==Machine learning models can be significantly improved by using feature engineering. The model can learn more from the raw data by transforming it into features that better reflect the problem. The model can also be made to avoid overfitting by removing redundant or irrelevant features. This will allow it to perform better on unseen data and increase its generalization performance. ==Explain Like I'm 5 (ELI5)==Feature engineering is similar to making a puzzle. We start with a box full of puzzle pieces. This is raw data. Then we sort through the pieces and find the ones that make a nice picture. This is similar to making a prediction. You might also need to modify the shape of pieces or combine pieces together. This is similar to changing the raw data into something the computer can understand. This will allow the computer to make better predictions about things that it hasn't seen before.{{Clickable button|Hello}}
