Probability & Statistics Chapter 2

Pareto Chart

A Pareto chart is a type of chart that contains both bars and a line graph, where individual values are represented in descending order by bars, and the cumulative total is represented by the line.

Bar Graph

A bar chart or bar graph is a chart that presents grouped data with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally.

Frequency Histogram

A bar graph of a frequency distribution in which the horizontal axis lists each unique value (or range of values) in a set of data, and the height of each bar represents the frequency (or relative frequency) of that value (or range of values).

Circle Graph

A circle graph is a circular chart divided into sections that each represent a percentage of the total.

Dot Plot

A dot chart or dot plot is a statistical chart consisting of data points plotted on a fairly simple scale, typically using filled in circles.

Stem-and-Leaf Plot

A plot where each data value is split into a "leaf" (usually the last digit) and a "stem" (the other digits).

Time Series Graph

A time series plot is a graph that you can use to evaluate patterns and behavior in data over time. A time series plot displays observations on the y-axis against equally spaced time intervals on the x-axis.

Class midpoint

Class Mark (Midpoint) The number in the middle of the class. It is found by adding the upper and lower limits and dividing by two. It can also be found by adding the upper and lower boundaries and dividing by two.

Cumulative Frequency

Cumulative frequency is defined as a running total of frequencies. The frequency of an element in a set refers to how many of that element there are in the set. Cumulative frequency can also defined as the sum of all previous frequencies up to the current point.

Frequency Polygon

Frequency polygons are a graphical device for understanding the shapes of distributions. They serve the same purpose as histograms, but are especially helpful for comparing sets of data. Frequency polygons are also a good choice for displaying cumulative frequency distributions.

Relative Frequency

To compute relative frequency, one obtains a frequency count for the total population and a frequency count for a subgroup of the population.

Frequency Distribution

a mathematical function showing the number of instances in which a variable takes each of its possible values.

Ogive

an ogive is a free-hand graph showing the curve of a cumulative distribution function. The points plotted are the upper class limit and the corresponding cumulative frequency. (which, for the normal distribution, resembles one side of an Arabesque or ogival arch).

Class Width

class width is the difference between the upper or lower class limits of consecutive classes. All classes should have the same class width.

Frequency

frequency count is a measure of the number of times that an event occurs.Frequency (or absolute frequency) of an event is the number of times the event occurred in an experiment or study. Frequencies are often graphically represented in histograms.

Sample Size

is the act of choosing the number of observations or replicates to include in a statistical sample and is an important feature of any empirical study in which the goal is to make inferences about a population from a sample.