QMS 102 Lecture Notes - Lecture 2: Frequency Distribution, Open Data Protocol, Decimal Mark

• School: Ryerson University
• Department: Quantitative Methods
• Course: QMS 102
• Professor: Nursel Ruzgar

Document Summary

Stem-and-leaf displays: a stem-and-leaf display conveys information about the following aspects of the data: identification of a typical or representative value. Extent of spread about the typical value. Presence of any gaps in the data. Extent of symmetry in the distribution of values. Rules and convention to construct a stem-and-leaf plot: the number of stems should be from 6 to 13 stems, the stem values should be consecutive numbers or repeated numbers. This order is reversed when the stems are negative values. Leaf rule #1: the leaf for each data value is the next single digit after the stem. When the stems are repeated twice, the leaves values 0 to 4 go to the first stem and the leaves values 5 to 9 go to the second stem of the same values. This order is reversed when the stems are negative. Leaf rules #4 and #5: leaf values must be evenly spaced, no commas or dashes between numbers are allowed.