Abstract
The goal of machine learning is to use data to create a predictive model. Machine learning models encapsulate a function to calculate an output based on one or more inputs. It creates a model from data.
Consists of two phases:
- Training — the process of defining the function.
- Inferencing — using the model to predict new values.
Training Machine Learning Models
Consider an ML model that predicts ice cream sales based on the weather:
- Training data comes from past observations.
- Features ($x$) — attributes of the thing being observed (temperature; rainfall; wind speed).
- Usually a vector: [$x_1, x_2, x_3, …$]
- Labels ($y$) — values (the number of ice creams sold on a day).
- Features ($x$) — attributes of the thing being observed (temperature; rainfall; wind speed).
- Algorithms are applied to the training data to find a relationship between the features and the labels and then generalize that relationship as a calculation.
- This is fitting the data to a function.
- The algorithm’s output ($\hat{y}$) is a model that encapsulates the calculation it performs as a function.