SY280 Lecture Notes - Lecture 5: Oldsmobile Toronado, Pie Chart, Central Tendency
Document Summary
Frequency: 17 people out of a total of 150. Categories in pie chart must exhaust all categories, categories must be small. Bar graphs used only for qualitative, bars do not touch each other. They touch because they show the continuity of the value. > used for small data sets, done manually. Used to shown the distribution of the variable. Stemplots: order from low (top) to high (bottom), 10s on left (stem) and 1s on right (leaf). Mean and median are meaningless in qualitative variables. Measure of central tendency: used in order to point to a central or typical value of a quantitative variable. The mode: the most frequently occurring value in a distribution. The mean: the result you get when you add up all of the observations and divide it by the total number of observations. The median: the mid-point of a distribution once you put it all in order (good measure of central tendency)
