Data Nominla Class

8/3/2019 Data Nominla Class

http://slidepdf.com/reader/full/data-nominla-class 1/28



Types of scales

Nominal scales

Ordinal scales

Interval scales Ratio scales



Measurement properties

Measurement is based on numbers

The properties of numbers are

Identity equality

Rank - order

Additivity add , sub.Mul , div



CHARACTERISTICS OF SCALESCHARACTERISTICS OF SCALES

DESCRIPTION ORDER

DISTANCE

ORIGIN



ANY DESCRIPTOR CAN BE USED FOR

RESPONSE

FOR INSTANCE, YES OR NO,FOR INSTANCE, YES OR NO,

AGREE OR DISAGREE AGREE OR DISAGREE THE NUMBER OF YEARS OF A RESPONDENTS AGE THE NUMBER OF YEARS OF A RESPONDENTS AGE

Male / femaleMale / female

Married / unmarried/ divorceMarried / unmarried/ divorce

Local /outstationLocal /outstation



ORDER

ORDER REFERS TO THE RELATIVE SIZESRELATIVE SIZES OF THE

DESCRIPTORS OR RELATIVE MAGNITUDE RELATIVE MAGNITUDE BETWEEN the LABELS, USED AS SCALE POINTS



HERE THE KEY WORD IS RELATIVE RELATIVE AND INCLUDES SUCH DESCRIPTORS AS

GREATER THAN GREATER THAN

LESS THAN LESS THAN AND EQUAL TO AND EQUAL TO



Important factors for measurement

Description

Order

A<b . a= b, a>b Distance

Difference between numbers

Orgin

Orgin starts from 0



Nominal scale

It is the simplest and lowest level of

measurement

Nominla means name This level involves dividing the variables and

assigning numbers

These categories dont have any particularorder

Numbers are assigned as just labels and have

no quantitative values



Classifies data according to a category only.

E.g., which color people select.

Colors differ qualitatively not quantitatively.

A number could be assigned to each color, but

it would not have any value.

The number serves only to identify the color.

No assumptions are made that any color has

more or less value than any other color.

Nominal scale



Assign subjects to groups or categories No order or distance relationship

No arithmetic origin

Only count numbers in categories

Only present percentages of categories

Chi-square most often used test of statistical

significance example : number of male

customers visited the shop

Nominal scale



Gender

Marital status Days of the week (months)

Geographic location Seasons

Types of restaurants

Religion-hindu , Muslim ,chris, sikis, others

Job type: executive, technical, clerical

Other examples

Coded as 0 Coded as 1



Which of t he follow ing media in fluences your pur chasing decisi ons t he most?

1 T el evisi on

2 Radi o

3 N ew s pa per s

4 Magazines

Nominal scale



Ordinal scale

In order

It has names like ordinal

scales and also have

something more

Order more to less

Or - higher to lower

The numbers are in rankorder

Example

Greater than

More desired

More difficult

Happier than

Higher than



Classifies data according to some order or

rank; e.g. names ordered alphabetically

With ordinal data, it is fair to say that one

response is greater or less than another.

E.g. if people were asked to rate the

hotness of 3 chili peppers, a scale of "hot",

"hotter" and "hottest" could be used. Values

of "1" for "hot", "2" for "hotter" and "3" for

"hottest" could be assigned.

Ordinal scale

The gap between the items is

unspecified.





Ordinal scale

Small medium large

Quality

Womens dress sizes

Examples

1 Padraig Harrington 116

2 Tiger Woods 78

3 Vijay Singh 62

4 Phil Mickelson 54

5 Sergio Garcia 54

6 Anthony Kim 46

7 Kenny Perry 42

8 Camilo Villegas 42

9 Trevor Immelman 30

10 Stewart Cink 14

Rank Player Points



Please rank the news programs offered in the following four networks based on your

preference.(1 for most preferred, 4 for least preferred).

_____ sun TV

_____ jaya TV

_____ z TV

_____ kalinar TV





assumes that the measurements are made in equal units.

i.e. gaps between whole numbers on the scale are equal.

e.g. Fahrenheit and Celsius temperature scales

an interval scale does not have to have a true zero. e.g. A

temperature of "zero" does not mean that there is no

temperature...it is just an arbitrary zero point. very cold

cant perform full range of arithmetic equations. 40 degrees is not

twice as hot as 20 degrees

permissible statistics: count/frequencies, mode, median, mean,

standard deviation

Interval scale



How likely are you going to buy a new automobile within the next six months? (Please

check the most appropriate category)

De f ini t ely w i ll not buy ___ 1

Probably w i ll not buy ___ 2

May or may not buy ___ 3

Probably w i ll buy ___ 4

De f ini t ely w i ll buy ___ 5

Interval scale



similar to interval scales except that

the ratio scale has a true zero value.

e.g. the time something takes

allows you to compare differencesbetween numbers.

permits full arithmetic operation.

if a train journey takes 2 hours and30 min, then this is half as long as a

journey which takes 5 hours.

R atio scale



All statistical techniques useable

Most powerful with most meaningful answers

Allows comparisons

R atio scale



0

1

2

3

4

5

6

7

Examples

height, weight, age,

length

time

income

market share

1.What is your annual inc ome be for e

t axes? $ _______

2. How f ar is your workpl ace from home?

_______ k i lometr es



Primary scales of measurement

4 81 9Nominal Numbers

assigned to

runners

Ordinal Rank order of

winners

Third

Place

Second

Place

First

Place

Interval Performancerating on a 0 to

10 Scale8.2 9.1 9.6

Ratio Time to finish in

seconds15.2 14.1 13.4



RELATIONSHIP BETWEEN SCALES AND SCALING PROPERTIES

SCALIN G PROPERTIESSCALIN G PROPERTIES

SCALE DESCRIPTION ORDER DISTANCE ORI GIN SCALE DESCRIPTION ORDER DISTANCE ORI GIN

NOMINAL YES NONOMINAL YES NO NONO NONO

ORDINAL YESORDINAL YES YESYES NONO NONO

INTERVAL YESINTERVAL YES YESYES YESYES NONO

RATIO YESRATIO YES YESYES YESYES YESYES





Facts About the Four Levels of Scales (contd)Facts About the Four Levels of Scales (contd)

Documents

Data Nominla Class