How to find quartiles & interquartile range (IQR) of data set using Casio Calculator STAT mode

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This is a repeat of the same example used in the last video where the quartiles and the interquartile range are calculated using the STAT mode on the Casio FX-82AU PLUS II scientific calculator. Note that the FX82AU PLUS does not have the functionality to compute Q1, Q2 (median) and Q3.
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The interquartile range (IQR) is a measure of statistical dispersion, specifically the range between the first quartile (Q1) and the third quartile (Q3) in a dataset. To find the interquartile range:
1. *Order the data:* Arrange the scores in ascending order from smallest to largest.
2. *Find Q1 and Q3:*
- Q1 is the median of the lower half of the dataset (excluding the overall median if the dataset has an odd number of observations).
- Q3 is the median of the upper half of the dataset.
3. *Calculate IQR:*
- IQR = Q3 - Q1
This range gives you an idea of the spread of the middle 50% of the data. It's a useful measure, especially when dealing with datasets that might have outliers, as it is less sensitive to extreme values than the range or standard deviation.