Notes › EENG 3421: Probability and Statistics for Engineers Lecture 23
Organization of Data
164 words 2 min Modified
Table of Contents
Raw Data
Data recorded in the sequence in which they are collected and before they are processed or ranked are called raw data Ungrouped data is raw data presented as a list of observations
Frequency and Relative Frequency
A frequency distribution of a qualitative variable lists all categories and the number of elements that belong to each category
Relative frequency of a category equals
$$ \text{relative frequency} = \frac{\text{frequency of that category}}{\text{sum of all frequencies}} $$Percentage equals
$$ \text{percentage} = (\text{relative frequency}) \cdot 100\% $$Graphical Displays
A graph made of bars whose heights represent the frequencies of respective categories is called a bar graph
A circle divided into portions that represent the relative frequencies or percentages of a population or sample belonging to different categories is called a pie chart
References
- Course lecture slides 22
Sources
- Course lecture slides 22