Book Image

Essential Statistics for Non-STEM Data Analysts

By : Rongpeng Li
Book Image

Essential Statistics for Non-STEM Data Analysts

By: Rongpeng Li

Overview of this book

Statistics remain the backbone of modern analysis tasks, helping you to interpret the results produced by data science pipelines. This book is a detailed guide covering the math and various statistical methods required for undertaking data science tasks. The book starts by showing you how to preprocess data and inspect distributions and correlations from a statistical perspective. You’ll then get to grips with the fundamentals of statistical analysis and apply its concepts to real-world datasets. As you advance, you’ll find out how statistical concepts emerge from different stages of data science pipelines, understand the summary of datasets in the language of statistics, and use it to build a solid foundation for robust data products such as explanatory models and predictive models. Once you’ve uncovered the working mechanism of data science algorithms, you’ll cover essential concepts for efficient data collection, cleaning, mining, visualization, and analysis. Finally, you’ll implement statistical methods in key machine learning tasks such as classification, regression, tree-based methods, and ensemble learning. By the end of this Essential Statistics for Non-STEM Data Analysts book, you’ll have learned how to build and present a self-contained, statistics-backed data product to meet your business goals.
Table of Contents (19 chapters)
1
Section 1: Getting Started with Statistics for Data Science
5
Section 2: Essentials of Statistical Analysis
10
Section 3: Statistics for Machine Learning
15
Section 4: Appendix

Performing proper sampling under different scenarios

The previous section introduced an example of misleading sampling in political polling. The correctness of a sampling approach will change depending on its content. When telephones were not accessible, polling by phone was a bad practice. However, now everyone has a phone number associated with them and, in general, the phone number is largely random. If a polling agency generates a random phone number and makes calls, the bias is likely to be small. You should keep in mind that the standard of judging a sampling method as right or wrong should always depend on the scenario.

There are two major ways of sampling: probability sampling and non-probability sampling. Refer to the following details:

  • Probability sampling, as the name suggests, involves random selection. In probability sampling, each member has an equal and known chance of being selected. This theoretically guarantees that the results obtained will ultimately...