Classifying and Displaying Data

7/28/2019 Classifying and Displaying Data

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QUANTITATIVE VARIABLEQUANTITATIVE VARIABLE

Grade point averageGrade point average

WeightWeight

AgeAge

Family incomeFamily income

Birth rateBirth rate

Number of children in a familyNumber of children in a family

VALUES ARE NUMERICAL IN NATURE


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QUANTITATIVE VARIABLEQUANTITATIVE VARIABLE

Discrete variable assume aDiscrete variable assume a

countable number of valuescountable number of values

No. of children 0, 1, 2, 3No. of children 0, 1, 2, 3

CLASSIFICATION

Continuous variable assumeContinuous variable assume

an infinite number of valuesan infinite number of values

Average grade 1.5, 2.0Average grade 1.5, 2.0


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QUALITATIVE VARIABLEQUALITATIVE VARIABLE

GenderGender

Political partyPolitical partyaffiliationaffiliation

OccupationOccupation

Religious preferenceReligious preference

Marital statusMarital status

Employment statusEmployment status

VALUES ARE CATEGORIES, NOT SUBJECT TO QUANTITATIVE

INTERPRETATION


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SCALE OF MEASUREMENTSCALE OF MEASUREMENT

NOMINAL SCALE onlyNOMINAL SCALE onlycategories, with neither numericalcategories, with neither numerical

quantity nor order impliedquantity nor order implied

GenderGender

Religious preferenceReligious preferenceOccupationOccupation

APPLIES TO QUANTITATIVE AND QUALITATIVE VARIABLES


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ORDINAL SCALE observations canORDINAL SCALE observations can

be ranked from smallest to largestbe ranked from smallest to largest

Outcome of a beauty contestOutcome of a beauty contest

Degrees of feeling or opinionDegrees of feeling or opinion

Professors performanceProfessors performance(poor, fair, average, good, excellent)(poor, fair, average, good, excellent)



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INTERVAL SCALE specifiesINTERVAL SCALE specifiesnumerical distance between thenumerical distance between the

valuesvalues

Intelligence quotientIntelligence quotient

TemperatureTemperature(no uniquely defined zeros)(no uniquely defined zeros)



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RATIO SCALE a line numberRATIO SCALE a line numberwith zero fixedwith zero fixed

WeightWeight

HeightHeight

IncomeIncome

Grade point averageGrade point average



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DATA PRESENTATIONDATA PRESENTATION

Textual MethodTextual Method

Data revealed that during schoolyear 2005-2006, out of the 350 total

enrollment in the OSEC, majority of

the students were superintendent,

and this is represented by 280 or

80.0%. Students with the rank of

major occupied the second largest

group .


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Tabular MethodTabular Method

Numerical information

displayed in a more

concise, systematic

manner in rows and

columns


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Graphical MethodGraphical Method

Data in visual form

such that quantitative

values are easily

conveyed and

comparison readily

available


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DISPLAYING NOMINAL/ORDINAL DATADISPLAYING NOMINAL/ORDINAL DATA

FREQUENCY TABLEFREQUENCY TABLE list of categories of list of categories ofthe nominal and ordinal data with associatedthe nominal and ordinal data with associatedfrequencyfrequency

DO YOU BELIEVE THAT THE POSSESSION OF A SMALL

AMOUNT OF MARIJUANA IS A CRIMINAL OFFENSE?

RESPONSE FREQUENCY

-----------------------------------------------

Yes 516

No 648

No opinion 36

-----------------------------------------------

TOTAL 1,200


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FREQUENCY TABLEFREQUENCY TABLEDO YOU BELIEVE THAT THE POSSESSION OF A SMALL


RESPONSE FREQUENCY RELATIVE FREQ.

-------------------------------------------------------------------------------

Yes 516 0.43

No 648 0.54

No opinion 36 0.03

-------------------------------------------------------------------------------

TOTAL 1,200 1.00


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FREQUENCY TABLEFREQUENCY TABLEDO YOU BELIEVE THAT THE POSSESSION OF A SMALL



Male Female Male Female

-------------------------------------------------------------------------------

Yes 294 222 0.420 0.444

No 385 263 0.550 0.526No opinion 21 15 0.030 0.300

-------------------------------------------------------------------------------

TOTAL 700 500 1.000 1.000


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FREQUENCY TABLEFREQUENCY TABLE

SURVEY TO RATE DORMITORY


-------------------------------------------------------------------------------

Very desirable 120 12%

Desirable 180 18%

Sufficient 360 36%

Livable 240 24%

Undesirable 100 10%

-------------------------------------------------------------------------------

TOTAL 1,000 100%


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Not exactly a form of frequency tableNot exactly a form of frequency table

Estimated rate (per 100,000 persons 12 years of age or

older) of personal victimization, United States, 1979.

Type of victimization Rate per 100,000

-----------------------------------------------------------------

Rape and attempted rape 145

Robbery 1,709

Assault 5,490

Personal larceny with contact 783

Personal larceny without contact 17,185

SOURCE: Sourcebook of Criminal Justice Statistics 1981,

p. 251, U.S. Department of Justice, Bureau of Justice

Statistics, Washington D.C.


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BAR GRAPH:BAR GRAPH:

simplest formsimplest form

160

FREQ. 120

80

40

Single Married Widowed

MARITAL STATUS

88

152

28


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PIE GRAPH:PIE GRAPH:

percentagepercentage

MARRIED

56.7%

SINGLE

32.8%

WIDOWED

10.4%


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DISPLAYING INTERVAL/RATIO DATADISPLAYING INTERVAL/RATIO DATA

FREQUENCY HISTOGRAMFREQUENCY HISTOGRAM

6

FREQ. 5

4

3

2

1

29.5 39.5 49.5 59.5 69.5 79.5 89.5 99.5

TYPING SCORES

1

3

4

1

2

6

2


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FREQUENCY DISTRIBUTIONFREQUENCY DISTRIBUTION

Grouped DataGrouped Data

Sturges Rule guide the number of classes to use

k = 1 + 3.3 log N

Where:

k = number of class intervals

N = total number of observations

log N = logarithm of N to the base 10

Range, R = maximum score minimum score

CLASS INTERVAL, c = R/k


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FREQUENCY DISTRIBUTIONFREQUENCY DISTRIBUTION

k = 1 + 3.3 log N

= 1 + 3.3 log 20 = 5.3

Range, R = 54 25 = 29

Class Interval, c = R/k

c = 29/5.3 = 5.4; say 5

AGE RAW DATAAGE RAW DATA

PNCOPNCO 4040 4040 3939 5454 3232 3535 3737 4444 5050 2525

PCOPCO 2828 3030 3535 4545 5252 5050 5353 2828 2525 3232

ClassClass

TallyTally

PNCOPNCO PCOPCO

Freq.Freq. %% Freq.Freq. %%

25 3025 30 11 1010 44 4040

31 3631 36 22 2020 22 2020

37 4237 42 44 4040 00 00

43 4843 48 11 1010 11 1010

49 5449 54 22 2020 33 3030

TotalTotal 1010 100100 1010 100100

Classifying and Displaying Data

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