Head First Data Analysis

Chapter 9. Histograms: The shape of numbers

How much can a bar graph tell you?

There are about a zillion ways of showing data with pictures, but one of them is special. Histograms, which are kind of similar to bar graphs, are a super-fast and easy way to summarize data. You’re about to use these powerful little charts to measure your data’s spread, variability, central tendency, and more. No matter how large your data set is, if you draw a histogram with it, you’ll be able to “see” what’s happening inside of it. And you’re about to do it with a new, free, crazy-powerful software tool.

Your annual review is coming up

You’ve been doing some really excellent analytical work lately, and it’s high time you got what’s coming to you.

The powers that be want to know what you think about your own performance.

Starbuzz Analyst Self-review

Thank you for filling out our self-review! This document is important for our files and will help determine your future at Starbuzz.

Note

Oh boy, a self evaluation.

Date	____________________
Analyst Name	____________________

Circle the number that represents how well-developed you consider your abilities to be. A low score means you think you need some help, and a high score means you think your work is excellent.

The overall quality of your analytical work.

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Your ability to interpret the meaning and importance of past events.

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Your ability to make level-headed judgements ...