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Variablesdr. Harun Al Rasyid, MPH

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Statistics is used to

describe / summarize data,identify associations &relationships, and maepredictions or!eneralizations.

Statistics is thecollection, or!anization& interpretation of data

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"

Statistics ispart of our

life, really#

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$

Statistics ispart of our

life, really#

% dari 10 wanita memilih shampoo ini'(

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)

Apa betul#

Siapa respondennya#

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*

+hat is A-A#

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 our date here our footer here

Ada berapa 0umlah daun

teratai# 1erapa lebardaun# Apasemua sama#

1erapa daunyan! ecil,sedan!,besar# 1erapa banya

atanya#

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ata adalahumpulan

fata

ihitun!

iuur

itimban!

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3nitial obser4ation

5enerate theory

5eneratehypothesis

6ollect data to testtheory

Analyze data

3dentify4ariables

Measure4ariables

ata

Research Process

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A 4ariable is acharacteristic of

the thin! you arestudyin! orobser4in!

Berat Panjang

 Jumlah

9ariables arecharacteristics thatcan be measured or

cate!orized

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9ariable

:umericRatio

3nter4al

6ate!ori

cal

:ominal

;rdinal

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Categorical 4ariables

A cate!orical 4ariable is made up ofcate!ories.

 -he data are counted.

<or e=ample> !ender ?male or female@, a!e!roup ?ids, teena!er, adults@, blood type ?A,

1, A1, or ;@, etc.

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7"

ebutan data sala ate!ori yan! Anda lihat

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7$

Continuous 4ariables

A continuous 4ariable is one that !i4es us ascore for each person and can tae on any4alue on the measurement scale that Be areusin!.

 -he data are measured.

C=ample> the hei!ht of students ?cm@,number of chairs in class, temperature,blood pressure, blood !lucose le4el, etc.

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7)

9ariables that are %named(, i.e.classiDed into one or more Eualitati4ecate!ories that describe thecharacteristic of interest

• no orderin! of the diFerent cate!ories

• no measure of distance betBeen4alues

• cate!ories can be listed in any orderBithout aFectin! the relationshipbetBeen them

Nominal 4ariable

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7*

3n medicine, nominal 4ariables are oftenused to describe the patient. C=amplesof nominal 4ariables mi!ht include>

• 5ender ?male, female@

• Cye color ?blue, broBn, !reen,hazel@

• Sur!ical outcome ?dead, ali4e@

• 1lood type ?A, 1, A1, ;@

Nominal 4ariable

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9ariables that ha4e an inherent order tothe relationship amon! the diFerentcate!ories

• an implied orderin! of the cate!ories?le4els@

• Euantitati4e distance betBeen le4els isunnoBn

• distances betBeen the le4els may not bethe same

• meanin! of diFerent le4els may not bethe same for diFerent indi4iduals

Ordinal 4ariable

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3n medicine, ordinal 4ariables oftendescribe the patientGs characteristics,attitude, beha4ior, or status. C=amplesof ordinal 4ariables mi!ht include>

• Sta!e of cancer ?sta!e 3, 33, 333, 39@

• Cducation le4el ?elementary, secondary,colle!e@

• Pain le4el ?mild, moderate, se4ere@

• Satisfaction le4el ?4ery dissatisDed,dissatisDed, neutral, satisDed, 4erysatisDed@

•A!reement le4el ?stron!ly disa!ree,disa!ree, neutral, a!ree, stron!ly a!ree@

Ordinal 4ariable

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9ariables that ha4e constant, eEualdistances betBeen 4alues, but the zeropoint is arbitrary.

C=amples of inter4al 4ariables>

• 3ntelli!ence ?3 test score of 788, 778,728, etc.@

• Pain le4el ?7I78 scale@

Interval 4ariable

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Ratio 4ariable

9ariables ha4e eEual inter4als betBeen4alues, the zero point is meanin!ful,and the numerical relationships

betBeen numbers is meanin!ful.C=amples of ratio 4ariables>

• +ei!ht ?)8 ilos, 788 ilos, 7)8 ilos,etc.@

• Pulse rate

• Respiratory rate

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Why

understandingtype of

variables isimportant

Memahami sala 4ariabelsan!at pentin! a!ar bisa

menentuan u0i statistic yan!tepat etia men!analisis

data. Sala 4ariabelmenentuan ba!aimana data

itu aan ditampilan ataudirin!as.

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Seoran! peneliti in!in melauan penelitian men!enai

berat bayi baru lahir dan 3M- ibu sebelum melahiran.

1erat bayi dielompoan men0adi 11JR dan :ormal,

sedan!an 3M- ibu dielompoan men0adi Abnormal dan

normal.

Apaah analisis data yan! palin! tepat untu di!unaan

pada penelitian tersebut#

a. orelasi spearmanb.6hi sEuare

c. K0i -

d.A:;9A

e. Re!resi

Contoh soal !"i