# Summarizing quantitative data

## Measuring center in quantitative data

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Statistics intro: Mean, median, & modeMean, median, & mode exampleCalculating the meanChoosing the "best" measure of centerMean, median, and mode review
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Mean, median, and modeGet 5 of 7 questions to level up!
Calculating the meanGet 3 of 4 questions to level up!
Calculating the medianGet 3 of 4 questions to level up!

## More on mean and median

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Comparing means of distributionsMeans and medians of different distributionsImpact on median & mean: removing an outlierImpact on median & mean: increasing an outlierMean as the balancing pointMissing value given the meanMedian & range puzzlers
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Calculating the mean: data displaysGet 3 of 4 questions to level up!
Calculating the median: data displaysGet 3 of 4 questions to level up!
Missing value given the meanGet 3 of 4 questions to level up!
Median & range puzzlersGet 3 of 4 questions to level up!

## Interquartile range (IQR)

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Interquartile range (IQR)Comparing range and interquartile range (IQR)Interquartile range review
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Interquartile range (IQR)Get 3 of 4 questions to level up!

## Variance and standard deviation of a population

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Measures of spread: range, variance & standard deviationVariance of a populationPopulation standard deviationThe idea of spread and standard deviationCalculating standard deviation step by stepMean and standard deviation versus median and IQRConcept check: Standard deviationStatistics: Alternate variance formulas
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Standard deviation of a populationGet 3 of 4 questions to level up!

## Variance and standard deviation of a sample

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Sample varianceSample standard deviation and biasPopulation and sample standard deviation review
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VarianceGet 3 of 4 questions to level up!
Sample and population standard deviationGet 3 of 4 questions to level up!

## More on standard deviation

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Why we divide by n - 1 in variance Simulation showing bias in sample varianceSimulation providing evidence that (n-1) gives us unbiased estimateUnbiased estimate of population varianceReview and intuition why we divide by n-1 for the unbiased sample variance

## Box and whisker plots

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Worked example: Creating a box plot (odd number of data points)Worked example: Creating a box plot (even number of data points)Constructing a box plotReading box plotsInterpreting box plotsBox plot reviewJudging outliers in a datasetIdentifying outliers with the 1.5xIQR rule
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Creating box plotsGet 3 of 4 questions to level up!
Reading box plotsGet 3 of 4 questions to level up!
Interpreting quartilesGet 3 of 4 questions to level up!
Identifying outliersGet 3 of 4 questions to level up!