Intro to Machine Learning
Introductory Vocabulary and Concepts
- Machine learning involves an input and output. The input can be one to multiple factors that mostly should be in numerical values. The output involves what one actually desires.
-
It is easiest to show and understand the predicted output with a scatterplot of this data. Visualizing it by plotting data and looking at relationships or regressions will help understanding.
-
​This indicates linear regression due to the linear relationship between the X and Y (input and output) and one can plot a line of best fit to predict further relationships. Where this line intersects the Y - axis can be seen as a bias.
-
Sometimes these relationships will be linear and the line of best fit will have a linear equation, called linear regression. Some of these relationships, on the other hand, may not be linear. For example, it could be exponential and this will be modeled by a different types of regression.
More Vocabulary:
-
Types of machine learning
-
Supervised - Includes a cluster of data that has a previous actual output.
-
Unsupervised - Training data without a previous actual output. In this situation the algorithm has no ideal output to begin with and may be more unpredictable. This website will involve mostly supervised learning.
-
Semi-supervised - Some outputs are the ones we would like
-
Reinforcement learning - Training a network towards a certain goal
-
-
Classification - Identifying categories to which something belongs
-
Regression - Relation between output and input
-
Probability estimation - Classification based on probability
-
Weights - Strength of connection of neurons. A higher magnitude of weights indicates a stronger connection. In predicting the price of a house, the amount of bedrooms/bathrooms might be a stronger indicator
-
Bias - An assumption made by a model to make the target function easier to approximate. Like the Y
-
Slope - Slope of the line of best fit that models the relationship between input and output
-
Features - variables in the problem set that have high enough weights to build an accurate predictive model
-
Label - What we are predicting
-
Linear Regression - when the relationship between the input and output is linear and can be predicted in a linear like fashion
-
Logistic regression - Model the probability of an event, easier to implement, efficient, and easy to train.
-
Cost - Difference between an predicted and actual