Outliers

Front

What is an outlier?

Back

An outlier is a data point that differs significantly from other observations in a dataset. It can skew the results of statistical analyses.

Front

What is the interquartile range (IQR)?

Back

The interquartile range (IQR) is a measure of statistical dispersion, calculated as the difference between the upper quartile (Q3) and lower quartile (Q1). It represents the range of the middle 50% of the data.

Front

How do you find the median of a data set?

Back

To find the median, arrange the data in ascending order and identify the middle value. If there is an even number of observations, the median is the average of the two middle values.

Front

What is the mode of a data set?

Back

The mode is the value that appears most frequently in a data set. A data set may have one mode, more than one mode, or no mode at all.

Front

What effect do outliers have on the mean?

Back

Outliers can significantly affect the mean, pulling it towards the outlier value and potentially misrepresenting the central tendency of the data.

Front

What is the upper quartile (Q3)?

Back

The upper quartile (Q3) is the median of the upper half of a data set, representing the 75th percentile.

Front

What is the lower quartile (Q1)?

Back

The lower quartile (Q1) is the median of the lower half of a data set, representing the 25th percentile.

Front

How do you calculate the range of a data set?

Back

The range is calculated by subtracting the smallest value in the data set from the largest value.

Front

What is a box plot?

Back

A box plot is a graphical representation of a data set that displays the median, quartiles, and potential outliers, providing a visual summary of the data distribution.

Front

What is the difference between mean and median?

Back

The mean is the average of all data points, while the median is the middle value when the data is ordered. The mean can be affected by outliers, whereas the median is more robust.