9.Data Analysis

8/2/2019 9.Data Analysis

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DATA ANALYSIS



Introduction

A body of methods that help to describe facts,

detect patterns, develop explanations, and test

hypothesis.



Stages of data analysis

Coding

Data entry

Descriptive analysis

Cross-tabulation

Testing relationships between variables



Coding

Summarised in

numbers or lettersfor easyidentification



Example of questionnaire

1. Gender

2. Age___________

3. Monthly expenditure

> RM 3006

RM 201 - RM 3005

RM 151 - RM 2004

RM 101 - RM 1503

RM 50 - RM 1002

< RM 501

4. Frequency of doing reference at library

Almost every day4

4-6 times a week3

2-3 times a week2

Once a week1

5. CGPA achievement__________________

6. Do you participate in sports?

No2

Yes1

Female2

Male1



Data entry

coded data isentered intocomputer

checked

cleaned/edited



Variable view



Measurement scale: nominal,ordinal and ratio

1. Jantina

2. Umur___________

3. Perbelanjaan bulanan

1 < RM 50

2 RM 50 - RM 100

3 RM 101 - RM 150

4 RM 151 - RM 200

5 RM 201 - RM 300

6 > RM 300

4. Kekerapan membuat rujukan diperpustakaan

1 Sekali seminggu

2 2-3 kali seminggu

3 4-6 kali seminggu

4 Hampir setiap hari

5. Pencapaian CGPA__________________

6. Aktif dalam aktiviti sukan

1 Ya

2 Tidak

1 Lelaki

2 Perempuan

NOMINAL

RATIO

ORDINAL

NOMINAL

RATIO

ORDINAL



Descriptive analysis

frequencydistribution

nominal and ordinalfrequencies

ratio/scaledescriptives

mean

mode

median



Cross-tabulation

relationshipbetween 2 or morevariables

use 3M method



3M to select suitable analysisprocedure

model

identify independent and dependentvariables

measurement

identify level of measurement: norminal,ordinal, ratio

method



Model

Frequency of doingreference at the library

CGPA

INDEPENDENT DEPENDENT

ORDINAL RATIO / SCALE



RATIO

Has a meaningful zero point(physical)

INTERVAL

Predetermine equalintervals, no true zero point

ORDINAL

Classifies and ranks objects

NOMINAL

Classifies objects intocategories

HeightWeightTimeSpeed

Scores-achievement, aptitude, IQ testTemperature

OpinionAcademic level

Income levelLiking

•True Categories

•ArtificialCategories

TasteGenderEthnicityColor

AreaOpinion

Measurement scale

http://www.animationlibrary.com/a-l/?n=image.php3&image_id=1270


















INDEPENDENT

DEPENDENT Nominal Ordinal Ratio / Scale

Nominal CROSSTABS CROSSTABS CROSSTABS

MEAN

DESCRIMINANT

Ordinal CROSSTABS CROSSTABS CROSSTABS

NONPAR CORR

DESCRIMINANT

Ratio/ scale MEANS

ANOVA

MANOVA

MEANS

ANOVA

MANOVA

CORRELATION

GRAPH

PARTIAL CORR

MANOVA

REGRESSION

Multivariate Analysis



RECODE: Transform-Recode-Into Different Variable

ANOVA: Analyse-General Linear Model-Univariate

CORRELATE: Analyse-Correlate-Bivariate

CROSSTABS: Analyse-Descriptive Statistics-Crosstabs

DESCRIPTIVES: Analyse-Descriptive Statistics-Descriptive

DESCRIMINANT: Analyse-Classify-Descriminant

FREQUENCIES: Analyse-Descriptive Statistics-Frequencies

MEAN: Analyse-compare mean-mean

MANOVA: Analyse-General Linear Model-Multivariate

SPEARMAN CORRELATION: Analyse-Correlate Bivariate

(Method=Spearman)

REGRESSION: Analyse regression-Linear (Method-Backward)

Analysis procedure for SPSS



Testing relationships between2 variables

Study relationship to determine indicator ofthe study concept

Significant relationships Degree/strengthM of relationship



Statistics that asses the strength of the relationship between

variables or the amount of variation in the dependentvariable that can be explained by the independent variable.



• Statistics that allow the researcher to determine or not arelationship is statistically significant (basically, anassessment or whether it is ‘real’ or or could have occurred

by chance)

Depends on

(Chadwick, 1984)

Strength of relationship &Sample size





ANALYSIS OF VARIANCE (ANOVA)•A procedure for deciding if a ratio level dependent variable is significantlyassociate with the nominal or dominant independent

CHI-SQUARE TEST•A test of statistical significance associate with contingency table analysis,where the dependent variable is a nominal one

CORRELATION ANALYSIS•A procedure for measuring how closely two ratio level variable co-varytogether

CORRELATION COEFFICIENT (r)•A measure of the strength of association between two variable, a correlationmay vary from + 1 to -1

DEGREE OF FREEDOM•Degree of freedom (df)= (Number of rows- 1) x (Number of column-1)

DEPENDENT VARIABLE

•A variable that is viewed as being influenced by other variable. Is the ‘effect’in a cause-effect relationship

INDEPENDENT VARIABLE•This variable is a ‘cause’ in a cause effect relationship. It is a variable which

has been selected as a possible influence on variations in a dependentvariable

Statistical terms










MEANThe mean is computed by summing the values of a variable anddividing the result by the total number of cases

MEDIANThe median represents the mid-point of a distribution

MODEThe most frequent occurring responses to a nominal variable

MULTIPLE REGRESSION ANALYSISAn analysis that identifies an equation to predict variations in an adependent variables

MULTIVARIATE ANALYSIS OF VARIENCE (MANOVA)

MANOVA is used in examining relations between a ratio level

dependent variable and dependent variables measured at any level.It also permit the researcher to examine multiple dependent variablessimultaneously.








NOMINAL MEASUREMENTA quantitative measure where the numbers are arbitrarily assigned to categoriesof the variable

ORDINAL MEASUREMENTMeasure where there is an order in the values assigned, but where the intervalsbetween the values are not equal

RATIO MEASUREMENTA qualitative measurement where intervals are equal and there is a true zeropoint.

REGRESSION ANALYSISA method for analyzing the relation between a ratio level dependent variable andindependent variables. This form of analysis provides weightings that may beused in an equation to describe the relationship, standardized weightings providea means for estimating the relative impact of independent variables on thedependent one

REGRESSION LINE

A straight line describing the relation between an independent and dependentvariable drawn so that the vertical deviations of the points above the line equal

the vertical deviations below the line.








SPEARMAN CORRELATION

The statistic is used to measure the strength of association between twoordinal level variables

PEARSON CORRELATIONThis statistics is used to measure the strength of association betweentwo ratio level variables

STANDARD DEVIATIONA measure that reflects the average amount of deviation from the meanvalue of the variable

TEST OF SIGNIFICANTA test reporting the probability that an observed association or differenceis the result of sampling fluctuations, and not reflective of some ‘real’

difference in the population from which the sample has been taken.

VARIABLESThose concepts that we intend to measure

VARIANCEVariance reflects the average amount of deviation from the mean value

of the variable, it is the standard deviation squared









Technical Report

Title page

Acknowledgement

TOC Abstract

Introduction

Methodology

Results and analysis

Discussion offindings

Recommendations

References

Appendix



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9.Data Analysis

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