SOCI 328 Lecture Notes - Lecture 5: Interquartile Range, Central Tendency, Quartile
Document Summary
How big the observations or values are "on average" Looking at several ways to asses/observe each of the aspects. Different ways of describing "typical" value of variable in sample. Most common indicators of centre/central tendency are mean, median, mode. Mean is sum of observations divided by number of observations. Can be highly influenced by observation that falls far from rest of data. Mean is not resistant measure of central tendency. Median is measurement that falls in middle of ordered sample, so that half of observations are larger and half are smaller. When sample size is odd, single measurement falls in middle. Center is not adequate description of distribution sometimes. Stats that describe variability/spread of variable in dataset called measures of dispersion. Median is measurement that falls in middle of ordered sample, so that half of observations are larger and half. Range is difference between largest and smallest observations. Inter- quartile range (iqr) is difference between first and third quartiles.
