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Summarizing 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
Practice
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!
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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!
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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!
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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!
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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!
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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
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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
Practice
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!
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Range and mid-rangeMean absolute deviation (MAD)Mean absolute deviation exampleMean absolute deviation (MAD) review
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Mean absolute deviation (MAD)Get 3 of 4 questions to level up!

About this unit

This unit covers common measures of center like mean and median. We'll also learn to measure spread or variability with standard deviation and interquartile range, and use these ideas to determine what data can be considered an outlier.