GEO E111 Lecture Notes - Lecture 27: Central Tendency
Document Summary
Techniques of analysing data: calculation of percentages. The table below shows the number of tourists who visited kenya from various parts of the world in 2006: calculate percentage increase of tourists from africa between 2005 and 2006, measures of central tendency. Outstanding general characteristics of the data: arithmetic mean. The middle value in a set of data arranged in order. M= (n+1)/2 (i) 20, 50, 90, 100, 150, 180, 200, 220, 240, 300, 360. (ii) 20, 50, 90, 100, 150, 180, 200, 220, 240, 300. Easy to calculate in a small data set. Easy to understand as it"s the value at the middle. Difficult to calculate in a large data set. Doesn"t show data distribution: calculation of ranges. Calculate the range of for the data above: mode. Most frequently recurring value in a set of data. Easy to find as no calculation is involved. Rarely used as a measure of central tendency.
