Statistics for business decision making and analysis robert stine and foster chapter 02

2.1 Data TablesSome Basic Ideas symbols with context with rows and columns attributes or variables form the columns... 2.2 Categorical and Numerical Data Categorical Data  Type of purch

Chapter 2

2.1 Data Tables

Some Basic Ideas

symbols with context

with rows and columns

attributes or variables form the columns

2.1 Data Tables

Disorganized Data

2.1 Data Tables

Same Data in a Data Table

2.1 Data Tables

formatting and units

2.2 Categorical and Numerical Data

Categorical Data

 Type of purchase made and Brand of bike are

examples

2.2 Categorical and Numerical Data

Numerical Data

 Size of bike (cm) and Amount spent ($) are

examples

2.2 Categorical and Numerical Data

subtracted (no absolute zero)

subtracted, multiplied or divided (makes ratio

comparisons possible)

2.2 Categorical and Numerical Data

Likert Scale (Ordinal – 5 to 7 Categories)

2.3 Recoding and Aggregation

(recoding price into expensive or inexpensive)

counting or summing values within categories

2.3 Recoding and Aggregation

An Example of Aggregation

4M Example 2.1: MEDICAL ADVICE

Motivation

Are patients from one HMO more likely to visit the doctor than those from another HMO?

4M Example 2.1: MEDICAL ADVICE

Method

Gather data and organize in a data table Cases

that make up the rows are office visits The

following variables make up three columns:

Patient ID; HMO Plan; and Duration of patient’s

office visit

4M Example 2.1: MEDICAL ADVICE

Mechanics

4M Example 2.1: MEDICAL ADVICE

Message

Aggregate the duration of office visits to learn

whether patients from one plan are consuming

most of the doctor’s office time

2.4 Time Series

Some Definitions

in chronological order

time series (e.g., daily, monthly, etc.)

2.4 Time Series

Timeplot of Monthly Unemployment Rate

2.5 Further Attributes of Data

Useful to Know

 When and where the data were collected

 Source of the data (available online?)

 How the data were collected

4M Example 2.2: CUSTOMER FOCUS

Motivation

How do customers in a focus group react to a

new product design?

4M Example 2.2: CUSTOMER FOCUS

Method

Gather data and organize in a data table The

cases that make up the rows are participants in

the focus group One of the variables that make

up the columns is participants’ ratings of the

product

4M Example 2.2: CUSTOMER FOCUS

Mechanics

In addition to product ratings, the columns should

name, age (in years), sex, and income

4M Example 2.2: CUSTOMER FOCUS

Message

Determine who likes the design (younger or more

affluent members of the focus group, for example) and choose advertising that appeals to this group

Best Practices