Yläkvarttiili

Yläkvarttiili, also known as the third quartile or Q3, is a statistical term representing the value below which 75% of the data falls in a sorted dataset. It is one of the three quartiles used to divide a dataset into four equal parts. The first quartile (Q1) is the value below which 25% of the data falls, and the median (Q2) is the value below which 50% of the data falls.

To calculate the yläkvarttiili, the dataset must first be arranged in ascending order. If the number of data points is odd, the median is the middle value. The yläkvarttiili is then the median of the upper half of the data, excluding the overall median. If the number of data points is even, the median is the average of the two middle values. The yläkvarttiili is the median of the upper half of the data, including the higher of the two middle values.

The yläkvarttiili is a measure of dispersion, indicating the spread of the upper 25% of the data. It is often used in conjunction with the alakvartiili (first quartile) to calculate the interquartile range (IQR), which is the difference between Q3 and Q1. The IQR provides a measure of the variability of the middle 50% of the data and is less sensitive to outliers than the range. The yläkvarttiili is a key component in constructing box plots, which visually represent the distribution of data, including quartiles, median, and potential outliers.