Book Image

Deep Learning from the Basics

By : Koki Saitoh
5 (1)
Book Image

Deep Learning from the Basics

5 (1)
By: Koki Saitoh

Overview of this book

Deep learning is rapidly becoming the most preferred way of solving data problems. This is thanks, in part, to its huge variety of mathematical algorithms and their ability to find patterns that are otherwise invisible to us. Deep Learning from the Basics begins with a fast-paced introduction to deep learning with Python, its definition, characteristics, and applications. You’ll learn how to use the Python interpreter and the script files in your applications, and utilize NumPy and Matplotlib in your deep learning models. As you progress through the book, you’ll discover backpropagation—an efficient way to calculate the gradients of weight parameters—and study multilayer perceptrons and their limitations, before, finally, implementing a three-layer neural network and calculating multidimensional arrays. By the end of the book, you’ll have the knowledge to apply the relevant technologies in deep learning.
Table of Contents (11 chapters)

The Pooling Layer

A pooling operation makes the space of the height and width smaller. As shown in Figure 7.14, it converts a 2 x 2 area into one element to reduce the space's size:

Figure 7.14: Procedure of max pooling

This example shows this procedure when 2 x 2 max-pooling is conducted with a stride of 2. "Max pooling" takes the maximum value of a region, while "2 x 2" indicates the size of the target region. As we can see, it takes the maximum element in a 2 x 2 region. The stride is 2 in this example, so the 2 x 2 window moves by two elements at one time. Generally, the same value is used for the pooling window size and the stride. For example, the stride is 3 for a 3 x 3 window, and the stride is 4 for a 4 x 4 window.

Note

In addition to max pooling, average pooling can also be used. Max pooling takes the maximum value in the target region, while average pooling averages the values in the target region. In image recognition...