Summarizing quantitative data

Measuring center in quantitative data

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Statistics intro: Mean, median, & mode
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Mean, median, & mode example
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Calculating the mean
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Choosing the "best" measure of center
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Mean, median, and mode review
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Practice

Mean, median, and modeGet 5 of 7 questions to level up!
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Calculating the meanGet 3 of 4 questions to level up!
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Calculating the medianGet 3 of 4 questions to level up!
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More on mean and median

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Comparing means of distributions
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Means and medians of different distributions
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Impact on median & mean: removing an outlier
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Impact on median & mean: increasing an outlier
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Mean as the balancing point
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Missing value given the mean
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Median & range puzzlers
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Practice

Calculating the mean: data displaysGet 3 of 4 questions to level up!
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Calculating the median: data displaysGet 3 of 4 questions to level up!
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Effects of shifting, adding, & removing a data pointGet 3 of 4 questions to level up!
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Missing value given the meanGet 3 of 4 questions to level up!
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Median & range puzzlersGet 3 of 4 questions to level up!
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Interquartile range (IQR)

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Interquartile range (IQR)
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Comparing range and interquartile range (IQR)
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Interquartile range review
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Interquartile range (IQR)Get 3 of 4 questions to level up!
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Variance and standard deviation of a population

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Measures of spread: range, variance & standard deviation
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Variance of a population
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Population standard deviation
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The idea of spread and standard deviation
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Calculating standard deviation step by step
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Mean and standard deviation versus median and IQR
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Concept check: Standard deviation
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Statistics: Alternate variance formulas
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Practice

Standard deviation of a populationGet 3 of 4 questions to level up!
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Variance and standard deviation of a sample

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Sample variance
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Sample standard deviation and bias
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Population and sample standard deviation review
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VarianceGet 3 of 4 questions to level up!
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Sample and population standard deviationGet 3 of 4 questions to level up!
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More on standard deviation

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Why we divide by n - 1 in variance
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Simulation showing bias in sample variance
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Simulation providing evidence that (n-1) gives us unbiased estimate
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Unbiased estimate of population variance
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Review and intuition why we divide by n-1 for the unbiased sample variance
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Box and whisker plots

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Worked example: Creating a box plot (odd number of data points)
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Worked example: Creating a box plot (even number of data points)
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Constructing a box plot
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Reading box plots
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Interpreting box plots
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Box plot review
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Judging outliers in a dataset
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Identifying outliers with the 1.5xIQR rule
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Practice

Creating box plotsGet 3 of 4 questions to level up!
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Reading box plotsGet 3 of 4 questions to level up!
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Interpreting quartilesGet 3 of 4 questions to level up!
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Identifying outliersGet 3 of 4 questions to level up!
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Other measures of spread

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Range and mid-range
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Mean absolute deviation (MAD)
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Mean absolute deviation example
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Mean absolute deviation (MAD) review
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Practice

Mean absolute deviation (MAD)Get 3 of 4 questions to level up!
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