2.5 Measures Of Central Tendency

Measures of central tendency the values around which set a set of the data tends to cluster.

There are several different kinds of calculations for central tendency; the kind of calculation that should be used depends on the type of data and purpose for which the central tendency is being calculated: But the three main types of central tendency are:
• Mean
• Mode
• Median

Mean: The sum of the values divided by the number of values—often called the "average."
• Add all of the values together.
• Divide by the number of values to obtain the mean.
• Example: The mean of 7, 12, 24, 20, 19 is (7 + 12 + 24 + 20 + 19) / 5 = 16.4.

Median: The value which divides the values into two equal halves, with half of the values being lower than the median and half higher than the median.
• Sort the values into ascending order.
• If you have an odd number of values, the median is the middle value.
• If you have an even number of values, the median is the sum of the two middle values divided by two.
• Example: The median of the same five numbers (7, 12, 24, 20, and 19) is 19.

Mode: The most frequently-occurring number.
• Calculate the frequencies for all of the values in the data.
• The mode is the value (or values) with the highest frequency.
• Example: For individuals having the following ages — 18, 18, 19, 20, 20, 20, 21, and 23, the mode is 20.

Outliers: points in a set of data that are significantly far from the majority of the other data.