Tag Archives: sample size

Regression Fantasies

Common Reasons for Doubting a Regression Model Finding a model that fits a set of data is one of the most common goals in data analysis. Least squares regression is the most commonly used tool for achieving this goal. It’s … Continue reading

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Polls Apart

Election season is fast approaching so you can be sure a plethora of polls will soon be adding to the mayhem. Polls educate us in two ways. They tell us what we, or at least the population being polled, think. … Continue reading

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Six Misconceptions about Statistics You May Get From Stats 101

When you learn new things, you can develop misconceptions. Maybe it’s the result of something you didn’t understand correctly. Maybe it’s the way the instructor explains something. Or maybe, it’s something unspoken, something you assume or infer from what was … Continue reading

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Grasping at Flaws

Even if you’re not a statistician, you may one day find yourself in the position of reviewing a statistical analysis that was done by someone else. It may be an associate, someone who works for you, or even a competitor. … Continue reading

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Secrets of Good Correlations

If you’ve ever seen a correlation coefficient, you’ve probably looked at the number and wondered, is that good? Is a correlation of -0.73 good but not a correlation of +0.58? Just what is a good correlation and what makes a … Continue reading

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You Can Lead a Boss to Data but You Can’t Make Him Think

The most carefully planned data analysis may not survive the intervention of a boss (or a client or other reviewer), whether well intentioned or not. Your aim may be to generate sound data and conduct a thorough and valid analysis, … Continue reading

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Ten Fatal Flaws in Data Analysis

1. Where’s the Beef? In a way, the worst flaw a data analysis can have is no analysis at all. Instead, you get data lists, sorts and queries, and maybe some simple descriptive statistics but nothing that addresses objectives, answers … Continue reading

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