Summarizing quantitative data

Progress
Measuring center in quantitative data
More on mean and median
Interquartile range (IQR)
Quiz 1
9 questions
Variance and standard deviation of a population
Variance and standard deviation of a sample
More on standard deviation
Quiz 2
5 questions
Box and whisker plots
Other measures of spread
Unit test
15 questions
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Lessons
Measuring center in quantitative dataMore on mean and medianInterquartile range (IQR)Quiz 1Variance and standard deviation of a populationVariance and standard deviation of a sampleMore on standard deviationQuiz 2Box and whisker plotsOther measures of spreadUnit test
Practice
Quizzes
Unit test
Measuring center in quantitative data
Learn
Statistics: The average
Statistics intro: Mean, median, & mode
Mean, median, & mode example
Calculating the mean
Choosing the "best" measure of center
Mean, median, and mode review
Practice
Mean, median, and mode
7 questions
Practice
Calculating the mean
7 questions
Practice
Calculating the median
57%
57%
Try again
More on mean and median
Learn
Comparing means of distributions
Means and medians of different distributions
Impact on median & mean: removing an outlier
Impact on median & mean: increasing an outlier
Mean as the balancing point
Missing value when the mean is given
Median & range puzzlers
Practice
Calculating the mean: data displays
4 questions
Practice
Calculating the median: data displays
4 questions
Practice
Effects of shifting, adding, & removing a data point
4 questions
Practice
Missing value given the mean
4 questions
Practice
Median & range puzzlers
4 questions
Practice
Interquartile range (IQR)
Learn
Interquartile range (IQR)
Comparing range and interquartile range (IQR)
Interquartile range review
Practice
Interquartile range (IQR)
4 questions
Practice
Identify your areas for growth in these lessons:
Measuring center in quantitative data
More on mean and median
Interquartile range (IQR)
Variance and standard deviation of a population
Learn
Measures of spread: range, variance & standard deviation
Variance of a population
Population standard deviation
The idea of spread and standard deviation
Calculating standard deviation step by step
Mean and standard deviation versus median and IQR
Concept check: Standard deviation
Statistics: Alternate variance formulas
Practice
Standard deviation of a population
4 questions
Practice
Variance and standard deviation of a sample
Learn
Sample variance
Sample standard deviation and bias
Population and sample standard deviation review
Practice
Variance
4 questions
Practice
Sample and population standard deviation
4 questions
Practice
More on standard deviation
Learn
Why we divide by n - 1 in variance
Simulation showing bias in sample variance
Simulation providing evidence that (n-1) gives us unbiased estimate
Unbiased estimate of population variance
Review and intuition why we divide by n-1 for the unbiased sample variance
Identify your areas for growth in these lessons:
Variance and standard deviation of a population
Variance and standard deviation of a sample
More on standard deviation
Box and whisker plots
Learn
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 plot
Reading box plots
Interpreting box plots
Box plot review
Judging outliers in a dataset
Identifying outliers with the 1.5xIQR rule
Practice
Creating box plots
100%
100%
Reading box plots
7 questions
Practice
Interpreting quartiles
7 questions
Practice
Identifying outliers
4 questions
Practice
Other measures of spread
Learn
Range and mid-range
Mean absolute deviation (MAD)
Mean absolute deviation example
Mean absolute deviation (MAD) review
Practice
Mean absolute deviation (MAD)
4 questions
Practice
Test your understanding of Summarizing quantitative data with these 15 questions.
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.