What is the difference between categorical and quantitative data?

Objective: SWBAT review for their first

quiz

Reminder

Your first quiz will take place on Wednesday!!! All slides, including ones for review, have been placed on the school website.

http://www.sfacs.us/classroom/high_school_classes__5-8_/uchenna_ngwudo/Statistics/

What is Statistics?

•Statistics is the study of the collection, organization, analysis, interpretation, and presentation of data.

Data

•Values of categorical or quantitative variables.

Sankofa Rewind: The 5 W’s

The W Question AnsweredWho The individuals or objects being observed

What Variables observed (Quantitative or Categorical)

When When observers collected the data

Where Where the observations took place

Why Why the observers have collected the data

Population• The term "population" represents all possible

measurements or outcomes that are of interest in a particular study.

Sample• The term "sample" refers to a portion of the population

that was studied.

Variables

•QUANTITATIVE Variables: measure either how much or how many of something.•CATEGORICAL Variables: name categories or answer questions about how cases fall.

A frequency table is a table that lists items and uses tally marks to record and show the number of times they occur.

Frequency Table

We record totals and category

names.

•Relative frequency tables display the data using the calculated percentages from our proportions.

Frequency Table

Bar Chart

A bar chart displays the distribution of a categorical variable, and shows the count for each category.A relative frequency bar chart displays the percentage of each category.

•A bad picture can distort your understanding of data.•The area principle states that the area occupied by a part of a graph should correspond to the size of the value it represents.

The Area Principle

Line Graphs

Line graphs depict changes in quantities over time.

Pie charts, used to display categorical data, slices a circle into pieces whose sizes are proportional to the fraction of the whole in each category.

Pie Charts (Circle Graph)