Chapter 2 - QMB2100 Flashcards
What is a frequency table?
A grouping of qualitative data into mutually exclusive and collectively exhaustive classes showing the number of observations in each class.
What are relative class frequencies?
A class frequency that shows the relationship between a class frequency and the total number of observations.
How do you find the relative class frequency?
You just need to divide the class frequency by the total of observations.
What is a bar chart?
A graph the shows qualitative classes on the horizontal axis and the class frequencies on the vertical axis. The class frequencies are proportional to the height of the bars.
What is the mode?
The class of a distribution with the highest frequency.
What is a pie chart?
A chart that shows the proportion or percentage that each class represents of the total number of frequencies.
What is a frequency distribution?
A grouping of quantitative data into mutually exclusive and collectively exhaustive classes showing the number of observations in each class.
How do you construct a frequency distribution table?
- Decide the number of classes.
- Determine the class interval.
- Set the individual class limits.
- Tally the data being observed into the classes and determine the number of observations in each class.
How do you decide the number of classes?
Using the rule 2^k > n; where “k” is the number of classes and “n” is the number of observations.
How do you determine the class interval?
Must cover at least the distance of the minimum value in the data up to the maximum value. The formula is i ≥ (Maximum value - Minimum value) / k; where “i” is the class interval and “k” is the number of classes.
What is the class frequency?
Is the number of observations in each class.
What is a relative frequency distribution?
Is a frequency distribution that shows the relationship between a class frequency and the total number of observations.
What is a histogram?
A chart where the classes are on the horizontal axis and the class frequencies on the vertical axis. The class frequencies are represented by the heights of the bar; however, quantitative data is continuous, so the horizontal axis represents all possible values and the bars are drawn adjacent to each other.
What is a frequency polygon?
It also shows the shape of the distribution, but it consists of line segments connecting the points formed by the intersections of the class midpoints and the class frequencies.
What is one advantage of the frequency polygon?
It allows us to compare directly two or more frequency distributions.
What is a cumulative frequency distribution?
It’s almost the same as a frequency distributions, but with the characteristic of adding the frequency of one lower class to the next class and so on.
