Lesson 2 & 3 - STAT 113 Class 2 Data and...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
S TAT 113 Class 2 Data and Measurement The Distribution of a Variable
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
O BJECTIVE A: D ATA What is data? Values , Labels , or Names that record/contain information about individuals in an orderly fashion, together with a context Example: Each row represents a different individual Each row can be referred to as a case
Background image of page 2
D ATA AND M EASUREMENT Each column represents a variable A variable is a property for which individuals of a certain type have a value We’ll call the following things values: What you’d normally call values (numbers, measurements) Labels Names
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
T WO TYPES OF VARIABLES Measurements With units Amounts Make sense to think about the “average” Examples: Height Weight #Bases stolen Miles per hour Types Labels Names Categories Examples: Gender Name Social Security # Favorite Color Quantitative Categorical
Background image of page 4
V ARIABLES There are two ways of thinking about the word “variable” Consider the variable height (in inches) 1. We can say that the variable height is a property of an individual (ie the distance from their feet and head while standing) 2. We can say that the variable height is an actual list of values , each value corresponding to an individual. In definition 1, a variable is more of a concept In definition 2, a variable contains data Definition 2 more closely corresponds with a column in a data table
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Q UANTITATIVE V ARIABLES : T WO T YPES Values are numbers, but cannot fall just anywhere within some range of values Examples: Number of stops a bus makes from Hunter to your home How many points a player scores in a basketball game Values are numbers, and can fall anywhere within some range of values Examples: Distance in feet from Hunter to your home The weight of a basketball Discrete Continuous
Background image of page 6
D ISCRETE VS C ONTINUOUS How can you tell the difference? Consider two individuals, each with a different value for some variables E.g. Tim and Tom are not the same height, and don’t have the same amount of change in their pockets. For continuous variables: No matter how close Tim’s value is to Tom’s, it’s possible that Tina, another person, has a value for this variable that’s between Tim’s and Tom’s For discrete variables: It’s possible that Tim’s and Tom’s values for these variables are so close, that Tina’s value couldn’t possibly be in between Tim’s and Tom’s
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
T INA IS TALLER THAN T OM , AND SHORTER THAN T IM 71 69 70 Tim Tom Tina
Background image of page 8
S UPPOSE T OM WERE TALLER … S TILL WE COULD IMAGINE A THIRD PERSON TALLER THAN T OM AND SHORTER THAN T IM 71 70 69.5
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
N O MATTER HOW CLOSE T IM AND
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 34

Lesson 2 & 3 - STAT 113 Class 2 Data and...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online