Data Quality in Practice - Focus Excel.

In this chapter, you'll learn the basics of using Excel that you need to structure and organize data in spreadsheets. Using a practical example on financial planning, you’ll learn everything you need to consider when creating an Excel file—for example, how to
properly format columns and cell values, and why it’s worth formatting important cell ranges as a table object.

You’ll apply formulas and functions for simple calculations and learn to distinguish between relative, absolute, and mixed cell references. You’ll learn how to use structured references to make your formulas even easier to understand and how to
filter and sort tables to get a better overview of your data.

In this chapter, you’ll learn how to summarize, analyze, and visualize data to gain insights—all in a way that’s as practical as possible!

We’ll examine data from an online course provider to answer questions about customer satisfaction, processing times, and participant backgrounds. Along the way, you’ll learn to use and interpret basic statistical metrics, pivot tables
and data slices for simple analyses. You’ll learn to use named ranges to make formulas easier to understand and conditional formatting to properly highlight key data points. With functions like VLOOKUP(), you’ll discover how to use Excel as an effective tool for organizing data. And, of course, in addition to key metrics and aggregated tables, you’ll also learn to use visualizations
effectively to understand your data.

At the end, an exciting mid-course project awaits you, where you can put all your data and Excel skills to the test once again.

This chapter focuses on ensuring data quality standards—at every stage of the value chain. You’re facing a new challenge: The data you worked with in Chapter 1 was clean and organized. Unfortunately, that’s often not the case in reality.
There are many reasons for this, which you should understand better.

In this chapter, you’ll therefore first learn about the dimensions of data quality—not just in theory, but in a practical way using real data in Excel. You’ll learn how to handle typical errors when importing data from various sources, how to clean data using the PowerQuery Editor, and how to ensure certain aspects of data quality—for example, through formula and data validation.
The analytical skills from Chapter 1 will also come into play here. The limitations of Excel will also be examined in more detail in this chapter.

At the end of the chapter, another exciting final project awaits you, in which you can further develop all the skills you’ve just learned.