Math 132B

Class 4

Data Collection

In each group:

1. Remember your group number

2. Introduce yourself to each other

3. Record the following information about each member:

• Name
• Class (Freshperson, Sophomore, …)
• Major
• College (ABS, Business, Education, HHS, SET)

• Favorite color
• Height
• Number of siblings
• Your group number

Structure of Data

• Data is organized in datasets.

• Dataset is a collection of values.

  • Numbers
  • “Strings” (pieces of text)
  • Special values (Yes/No, True/False, …)

• Each value belongs to exactly one variable and exactly one observation.

• A variable contains all values that measure the same attribute or property of all observational units.

• An observation contains all values that measure attributes or properties of the same observational unit.

Observational Units

• In the data you just collected:

• In the following situation:

  For a group of 30 patients, temperature, pulse and blood pressure are measured every 4 hours.

• Phone numbers of multiple people are recorded. Each person may have multiple phone numbers (home, cell, work, …)

Variables

• In the data you just collected:

• In the following situation:

  For a group of 30 patients, temperature, pulse and blood pressure are measured every 4 hours.

• Phone numbers of multiple people are recorded. Each person may have multiple phone numbers (home, cell, work, …)

Name

Class

(Freshperson, Sophomore, …)

Major

College

(ABS, Business, Education, HHS, SET)

Favorite color

Height

Number of siblings

Group number

Types of Variables

Types of Variables

• Name
• Class
• Major
• College
• Favorite color
• Height
• Number of siblings
• Your group number