Author: Alan

You’ll work with frequency tables in order to see the range of values in your data. You’ll use graphical tools like histograms, stem and leaf plots, and boxplots to get a visual picture of how the data values are distributed. You’ll learn about descriptive statistics that reduce the contents of your data to a few values, such as the mean and standard deviation. Applying these tools is the fi rst step in the process of evaluating and interpreting the contents of your data set. Variables and Descriptive Statistics In this chapter you’ll learn about a branch of statistics called descriptive…

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Up to now, you’ve used tools such as frequency tables, descriptive statistics, and scatter plots to describe and summarize the properties of your data. Now you’ll learn about probability, which provides the foundation for understanding and interpreting these statistics. You’ll also be introduced to statistical inference, which uses summary statistics to help you reach conclusions about your data. Probability Much of science and mathematics is concerned with prediction. Some of these predictions can be made with great precision. Drop an object, and the laws of physics can predict how long the object will take to fall. Mix two chemicals, and…

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This chapter examines the relationship between two variables using linear regression and correlation. Linear regression estimates a linear equation that describes the relationship, whereas correlation measures the strength of that linear relationship. Simple Linear Regression When you plot two variables against each other in a scatter plot, the values usually don’t fall exactly in a perfectly straight line. When you perform a linear regression analysis, you attempt to fi nd the line that best estimates the relationship between two variables (the y, or dependent, variable, and the x, or independent, variable). The line you fi nd is called the fi…

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Becoming a software architect isn’t something that simply happens overnight or with a promotion. It’s a role, not a rank. It’s the result of an evolutionary process where you’ll gradually gain the experience and confidence that you need to undertake the role. While the term “software developer” is fairly well understood, “software architect” isn’t. Here are the things that I consider to make up the software architecture role. Notice that I said “role” here; it’s something that can be performed by a single person or shared amongst the team. 1. Architectural Drivers The first part of the role is about…

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In this chapter you’ll learn how to work with Excel 2007 in the Windows operating system. You’ll be introduced to basic workbook concepts, including navigating through your worksheets and worksheet cells. This chapter also introduces Stat Plus, an Excel add-in supplied with this book and designed to expand Excel’s statistical capabilities. Getting Started This book does not require prior Excel 2007 experience, but familiarity with basic features of that program will reduce your start-up time. This section provides a quick overview of the features of Excel 2007. If you are using an earlier version of Excel, you should refer to…

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Software architecture then, is it important? The agile and software craftsmanship movements are helping to push up the quality of the software systems that we build, which is excellent. Together they are helping us to write better software that better meets the needs of the business while carefully managing time and budgetary constraints. But there’s still more we can do because even a small amount of software architecture can help prevent many of the problems that projects face. Successful software projects aren’t just about good code and sometimes you need to step away from the code for a few moments…

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This part of the book is about the overall process of designing software, specifically looking at the things that you should really think about before coding. Architectural drivers Regardless of the process that you follow (traditional and plan-driven vs lightweight and adaptive), there’s a set of common things that really drive, influence and shape the resulting software architecture. Functional requirements In order to design software, you need to know something about the goals that it needs to satisfy. If this sounds obvious, it’s because it is. Having said that, I have seen teams designing software (and even building it) without…

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As we explain programming for the web to you, it’s helpful for all of us to speak the same language, at least when it comes to the subject at hand. Knowing how the web works, at least at a high level, will pay dividends when you start creating sites that will work on it. Granted, you don’t need to know how a car works before driving, but knowing how the steering wheel, throttle, and brakes all relate to make the vehicle move is especially important to keep you from hitting things. So consider what you’re about to read as driver’s…

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Do you dream? Do you watch people around you going about their daily tasks, and wonder how they’re able to achieve things you can’t, be more effective than you can be, or have more time for enjoyment? You’re not alone: at some point, everybody will have watched another person achieve what they would consider to be almost impossible. This happens on a macro level when we see explorers heading into the vast unknowns of the Arctic or the Himalayas. Getting Familiar with Windows 10 Windows 10seems like the logical place to begin this journey. It’s the workspace in which everything…

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You have no doubt changed the desktop wallpaper on your PC, probably many times. This means you know you can right-click in any blank space on the desktop to access the Personalization options. Did you know that’s there’s much more that you can do to make your desktop a more pleasurable space in which to work? Personalizing the Lock Screen Let’s start with those Personalization options. They open the Settings app (or panel), which you can also open by clicking the “gear” icon on the bottom left of the Start menu. On the left, you see the main Settings categories.…

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