this presentation is about common error that we conduct during our research work due to lack of knowledge about statistical techniques

2. Data Analysis
Techniques & Statistical Software's
By
Dr.Ammara Khakwani
In
Numl Multan Campus

3.  Estimation
 Prediction
 Forecasting
For the purpose of
 Decision making
 about unknown parameters
 on the basics Estimates

4. Problem
Design
Data analysis
Summary

6.  Process data and report the overall trends.
 Process Systematically
 Apply Statistical Techniques to describe and
evaluate data.

7.  Not Having the necessary skills to analyze
 Not Following acceptable norms for data analysis
 Not Choosing the appropriate statistical software
 Not Providing honest and accurate analysis
 Lack of sense for data presentation
 Extended data analysis

8. Getting data ready for analysis
Coded
Transcribe data
from
Questionnaire
Response
No
Response
Keyed
software
first column for
identification
purposes
method
Edited
check 10% of
questionnaires
systematic
sampling

9. keyed
To compare the data in the
data file with the answers of
the participants
Enter this number in the first
column of your data file
Write this number on
the first page of every
questionnaire
• Assign a number to every
questionnaire

11. Solution for non-responses
Assign a number give a
code in questionnaire
Give a mean value to all those who
have responded
Look at participants
pattern of responses
deduce a logical answer

12. Summary
Figure Measures
Measures of
Central Tendency
Measures of
Dispersion
Visual
Reprsentation
Graphs

13. Scale Examples Measures of
Central
Tendency…
for a single
Variable
Measures of
Dispersion …for
a Single variable
Visual
Summary
…for a single
variable
Measure of
Relation …
between
variables
Visual
Summary of
Relation …
between
variables
Nominal Social security
number gender
Mode ____ Bar chart, pie
chart
Contingency
table
(cross-tab)
Stacked bars,
clustered bars
Ordinal Satisfaction rating
on a 5-point scale
(1=not satisfied at
all,5=extremely
satisfied
Median Semi-inter
Quartile Range
Bar chart pie
chart
Contingency
table
(cross-tab)
Stacked bars,
clustered bars
Interval Age
15-20
Height
5-6 feet
Arithmetic
Mean
Minimum,
maximum,
Standard
Deviation,
Variance,
Co-efficient of
variation
Histogram,
scatter plot,
x-and-whisker
plot
Correlations Scatters plots
Ratio sales Arithmetic or
Geometric
mean
Same as above Histogram,
Scatter plot,
x-and-whisker
plot
Correlations Scatters plots

14. Relationship
between Variables
Significance of
Bivariate Relationship
Interval Scale
Ordinal
Scale
Nominal
Scale
Nature Direction

15. Ordinal
scale
Spearman’s
Rank correlation
Kendall’s
Rank correlation
Nominal
scale
χ²-test
Interval
scale
Spearman’s
rank correlation
Kendall’s rank
correlation

16. 1. Reliable
2. Well documented
3. User-friendly
4. General
5. Flexible
6. Fast

18.  1. How Easy Is the Statistical Software to Use?
2. Depth of menued procedures.
3. Range and quality of use of procedures offered.
4. Modifiability of analytical output.
5. Ease of table output to formatting .
6. Range of Graphical output offered.
7. Speed of handling large data sets.
8. Ease of results & flexibility of data set manipulation.

19. Education researches,
Government,
Marketing Organizations
Telecommunications,
Banking,
Finance,
Insurance,
Healthcare,
Manufacturing,
Retail,
Consumer packaged goods,

21.  Transform raw data into information.
 Provide a way of drawing inductive
inferences from data.
 Distinguishing the signal from the statistical
fluctuations present in the data.
 Statistical procedures are categorized
according to Descriptive, and inferential
Statistics .

22.  For the Social Sciences (SPSS))
 Statistical Analysis System (SAS)
 Econometric Views (EViews)
 MINITAB
 STATA
 R & MATLAB
 MS-EXCEL

23.  MiniTab -- a powerful, full-featured MS
Windows , with coverage of industrial quality
control analyses.
 EasySample -- a tool for statistical sampling.
 SAS/STAT http://www.sas.com/ from
descriptive statistics, t-tests, analysis of
variance, and predictive modeling to exact
methods

24.  ATLAS.ti http://www.atlasti.com/ ATLAS.ti
serves as a powerful utility for qualitative
analysis,
 CDC EZ Text
http:/www.cdc.gov/hiv/topics/surveillance/res
ources/software/ez-text/index.htm CDC EZ-
Text is developed to assist researchers
create, manage, and analyze semi-structured
qualitative databases.
 NVivohttp://www.qsrinternational.com/
is designed to support a wide range of
research methods,

25. Statistical Package for the Social Science
 Statistical Product and Service Solutions
Popular statistical packages Complex
Data manipulation and analysis with
Simple instructions

26.  SPSS can take data from almost any type of
file and use them to generate tabulated
reports, charts, and plots of distributions and
trends, descriptive statistics, and conduct
complex statistical analyses.

27. Questions in the questionnaire are
mapped into Variables in SPSS

28. How is your satisfaction with the customer
service of the staff of Bata?
O Excellent
O Good
O Bad
O Very bad
Missing value

29. 1 = Excellent
2 = Good
3 = Bad
4 = Very bad
5 = missing value

30. Please indicate your gender.
O Female
O Male
Codes:
1 = Female
2 = Male
3 = missing value

31. What is your average expenditure in the
restaurant on a weekly basis?
……… rupees per week .
For how many years have you been registered
as a student at B.Z University?
……… year(s)

32.  I would like to have the assortment
extended with the following products:
…………………………………………
 Processed by
Coding manually afterwards

33.  Description
 Order
 Distance
 Nominal
 Ordinal
 Scale
Levels of Measurement

34. Nominal
 Smoker or non smoker (yes, no);
Ordinal
In your opinion, would you say the prices at Chen-
one are
O Higher than Cantt. Bazar
O About the same as Cantt.
O Lower than Cantt.
Ordinal
What is your age?
O 15–<25
O 25–<40
O 40–<60
O 60–<90

35.  Analyze
 Frequencies
 Cross tabs
 Tables
 Graphs
 Bar
 Pie
 Histogram
 Line
 Boxplot
Don’t forget to save
◦ Data file
◦ Output file

36.  Input data into the computer
 Organise data
 Compare data
 Manage data
 Summarise data (transform raw data into
information)
 Generate tables and graphs
 Facilitate presentation of information and
preparation of analytical reports

37.  Start → All Programs → SPSS Inc→ SPSS 16.0 →
SPSS 16.0

38.  The default window will have the data editor
 There are two sheets in the window:
1. Data view 2. Variable view

40. Data View

41. Variable View

42. Variable view
◦ Name
◦ Type (Numeric)
◦ Label
◦ Values (= the codes of the answers)
◦ Measure (= Level of Measurement)

43.  Data Editor
Spreadsheet-like system for defining, entering, editing, and
displaying data. Extension of the saved file will be “sav.”

44.  Output Viewer
Displays output and errors. Extension of the saved file will be “spv.”

45.  Syntax Editor
Text editor for syntax composition. Extension of the saved file will be
“sps.”

46.  Script Window Provides the opportunity to write full-blown programs, in
a BASIC-like language.

47. This sheet is visible when you first open the Data Editor and this sheet
contains the data -------------------Click on the tab labeled Variable View
Click

48. This sheet contains information about the data set .The first character of the
variable name must be alphabetic .Variable names must be unique, and
have to be less than 64 characters. Spaces are NOT allowed.

49. ◦ Click on the ‘type’ box. The two basic types of variables that you will use are
numeric and string. This column enables you to specify the type of variable.

50. Width allows you to determine the number of
characters SPSS will allow to be entered for the
variable

51. ◦ Number of decimals
◦ It has to be less than or equal to 16
3.14159265

52. _You can specify the details of the variable
◦ You can write characters with spaces up to 256 characters

53. This is used and to suggest which numbers represent which
categories when the variable represents a category

54.  Click the cell in the values column as shown below
 For the value, and the label, you can put up to 60 characters.
 After defining the values click add and then click OK.
Click

55.  How would you put the following information into SPSS?
Value = 1 represents Male and Value = 2 represents
Female
Name Gender Height
JAUNITA 2 5.4
SALLY 2 5.3
DONNA 2 5.6
SABRINA 2 5.7
JOHN 1 5.7
MARK 1 6
ERIC 1 6.4
BRUCE 1 5.9

56. Click

57. Click

58.  To save the data file you created simply click ‘file’ and click ‘save as.’
You can save the file in different forms by clicking “Save as type.”
Click

59.  Click ‘Data’ and then click Sort Cases

60.  Double Click ‘Name of the students.’ Then click
ok.
Click
Click

61.  How would you sort the data by the
‘Height’ of students in descending order?
 Answer
◦ Click data, sort cases, double click ‘height of
students,’ click ‘descending,’ and finally click ok.

62.  Click ‘Transform’ and then click ‘Compute Variable…’

63.  Example: Adding a new variable named ‘lnheight’ which is
the natural log of height
◦ Type in lnheight in the ‘Target Variable’ box. Then type in
‘ln(height)’ in the ‘Numeric Expression’ box. Click OK
Click

64.  A new variable ‘lnheight’ is added to the table

65.  Create a new variable named “sqrtheight”
which is the square root of height.
 Answer

66.  Frequencies
◦ This analysis produces frequency tables showing
frequency counts and percentages of the values of
individual variables.
 Descriptives
◦ This analysis shows the maximum, minimum, mean,
and standard deviation of the variables
 Linear regression analysis
◦ Linear Regression estimates the coefficients of the
linear equation

67.  Open ‘Employee data.sav’ from the SPSS Go to “File,” “Open,”
and Click Data

68.  Go to Program Files,” “SPSSInc,” “SPSS16,” and “Samples”
folder.
 Open “Employee Data.sav” file

69.  Click ‘Analyze,’ ‘Descriptive statistics,’ then click ‘Frequencies’

70.  Click gender and put it into the variable box.
 Click ‘Charts.’
 Then click ‘Bar charts’ and click ‘Continue.’
Click Click

71.  Finally Click OK in the Frequencies box.
Click

73.  Click ‘Analyze,’ ‘Descriptive statistics,’ then click ‘Frequencies.’
 Put ‘Gender’ in the Variable(s) box.
 Then click ‘Charts,’ ‘Bar charts,’ and click ‘Continue.’
 Click ‘Paste.’
Click

74.  Highlight the commands in the Syntax editor
and then click the run icon.
 You can do the same thing by right clicking the
highlighted area and then by clicking ‘Run
Current’
Click
Right
Click!

75.  Do a frequency analysis on the
variable “minority”
 Create pie charts for it
 Do the same analysis using the
syntax editor

77. Click

78.  Click ‘Analyze,’ ‘Descriptive statistics,’ then click
‘Descriptives…’
 Click ‘Educational level’ and ‘Beginning Salary,’ and put it into
the variable box.
 Click Options
Click

79.  The options allows you to analyze other descriptive
statistics besides the mean and Std.
 Click ‘variance’ and ‘kurtosis’
 Finally click ‘Continue’
Click
Click

80.  Finally Click OK in the Descriptives box. You will be able to
see the result of the analysis.

81.  Click ‘Analyze,’ ‘Regression,’ then click ‘Linear’
from the main menu.

82.  For example let’s analyze the model
 Put ‘Beginning Salary’ as Dependent and ‘Educational Level’ as
Independent.
  edusalbegin 10
Click
Click

83.  Clicking OK gives the result

84.  Click ‘Graphs,’ ‘Legacy Dialogs,’ ‘Interactive,’ and
‘Scatterplot’ from the main menu.

85.  Drag ‘Current Salary’ into the vertical axis box and ‘Beginning
Salary’ in the horizontal axis box.
 Click ‘Fit’ bar. Make sure the Method is regression in the Fit box.
Then click ‘OK’.
Click
Set this to
Regression!

88. Click on the “fit” tab to make sure the method is regression

90. Descriptive Statistics (Summarising Data)
 Frequency Distributions
◦ Frequency tables
◦ Histograms
 Central Tendency
◦ The mean
◦ The median
◦ The mode
 Variance (spread of data around the mean)
 The range
 Standard deviation

91. Skewness refers to the degree and direction of asymmetry in a distribution.
No Skew
Positively Skewed Negatively Skewed

92.  The reliability of a scale indicates how free it
is from random error.
 Two frequently used indicators of a scale’s
reliability are test-retest
 reliability (also referred to as ‘temporal
stability’) and internal consistency.

93. •Do not simply accept and report the
format of SPSS computer printout.
•Instead, reformat the data into tables.
•
•Take some care in reporting tables.
•Provide informative titles.
• Be sure to include the Ns