Using RBMs in a machine learning pipeline
Of course, we want to see how the RBM performs in our machine learning pipelines to not just visualize the workings of the model, but to see concrete results of the feature learning. To do this, we will create and run three pipelines:
- A logistic regression model by itself running on the raw pixel strengths
- A logistic regression running on extracted PCA components
- A logistic regression running on extracted RBM components
Each of these pipelines will be grid-searched across a number of components (for PCA and RBM) and the C
parameter for logistic regression. Let's start with our simplest pipeline. We will run the raw pixel values through a logistic regression to see if the linear model is enough to separate out the digits.
Using a linear model on raw pixel values
To begin, we will run the raw pixel values through a logistic regression model in order to obtain something of a baseline model. We want to see if utilizing PCA or RBM components will allow the...