PNB 2XE3 Lecture Notes - Lecture 2: Level Of Measurement, Central Tendency, Box Plot
13 Feb 2018
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In class exercise (mean, median and mode: 1. N is number of scores 1 year olds: 12 3 year olds: 15: 2. Increase sample size, report values for longer than 24 h, time spent crying instead of number of times cried, make sample random. Mean: sum of the scores divided by the number of scores, can be manipulated algebraically, sample means are more stable than medians or modes, may not exist in data. Interpretation requires some faith in interval properties of the data iclicker q 1 | central tendency: a. Trimmed means: discard a percentage of scores, remove a fixed % off each end, makes the means more representative, lose a lot of data. Variability/dispersion: the degree to which individual data points are distributed around the mean. Range: measure of distance from lowest to highest score, con: totally reliant upon extreme values, can be affected by outliers, range is the distance between top and bottom.
