Book Image

Data Forecasting and Segmentation Using Microsoft Excel

By : Fernando Roque
Book Image

Data Forecasting and Segmentation Using Microsoft Excel

By: Fernando Roque

Overview of this book

Data Forecasting and Segmentation Using Microsoft Excel guides you through basic statistics to test whether your data can be used to perform regression predictions and time series forecasts. The exercises covered in this book use real-life data from Kaggle, such as demand for seasonal air tickets and credit card fraud detection. You’ll learn how to apply the grouping K-means algorithm, which helps you find segments of your data that are impossible to see with other analyses, such as business intelligence (BI) and pivot analysis. By analyzing groups returned by K-means, you’ll be able to detect outliers that could indicate possible fraud or a bad function in network packets. By the end of this Microsoft Excel book, you’ll be able to use the classification algorithm to group data with different variables. You’ll also be able to train linear and time series models to perform predictions and forecasts based on past data.
Table of Contents (19 chapters)
1
Part 1 – An Introduction to Machine Learning Functions
5
Part 2 – Grouping Data to Find Segments and Outliers
10
Part 3 – Simple and Multiple Linear Regression Analysis
14
Part 4 – Predicting Values with Time Series

Statistical significance of the slope

Remember that the slope determines the relationship between the X and Y variables.

To check the significance of the slope of the variables' relationship and the viability to build a predictive model, we are going to use the t-test. The t-test requires two hypotheses:

  • H0 – null hypothesis: The slope equals zero. This means that there is no relationship between the variables.
  • HA – alternative hypothesis: The slope is NOT equal to zero. This means that the variables have a relationship.

The t-test calculation steps are as follows:

  1. Calculate the s value by dividing the SSE by the number of data elements minus two. In this example, the number of elements of data is 159.
  2. Divide the slope by the s value.
  3. Check whether the t-test is greater than the critical value given by the t-test table (https://www.sjsu.edu/faculty/gerstman/StatPrimer/t-table.pdf). If the value is greater than the critical...