Statistics
RESEARCH
• STATISTICS
RESEARCH
Pre-positivistic
positivistic
positivistic
Initial Observation
(research Question)
Data
Generate Theory
Generate Hypothesis
Identify Variables
Generate Hypothesis
Collect data to test theory
Identify Variables
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VALIDATING YOUR
INSTRUMENTS
INSTRUMENTS
QUESTIONNAIRE
AND
What is the relationship between you
instrument and data?
Instrument
Instrument
• Valid
• Not valid
VALIDITY
What is validity?
How do you validate your
instruments?
• Expert judgment
• Using computer software
– Questionnaire: items: SPSS
– Questionnaire: items: SPSS
So?
COMMON MISTAKES
• NO TRY OUT--
INVALID
INTRUMENT ---
INVALID DATA
Go to the library
Find a thesis which used a questionnaire
as one of the instruments in collecting the
as one of the instruments in collecting the
data.
Data
Data
Qualitative Data
Qualitative Data
Quantitative Data
Quantitative Data
Tabular
Tabular
Methods
Methods
Tabular
Tabular
Methods
Methods
Graphical
Graphical
Methods
Methods
Graphical
Graphical
Methods
Methods
••Frequency
Frequency
Distribution
Distribution
••Rel. Freq. Dist.
Rel. Freq. Dist.
••% Freq. Dist.
% Freq. Dist.
••Crosstabulation
Crosstabulation
••Bar Graph
Bar Graph
••Pie Chart
Pie Chart
••Frequency
Frequency
Distribution
Distribution
••Rel. Freq. Dist.
Rel. Freq. Dist.
••Cum. Freq. Dist.
Cum. Freq. Dist.
••Cum. Rel. Freq.
Cum. Rel. Freq.
Distribution
Distribution
••Stem
Stem--and
and--Leaf
Leaf
••Dot Plot
Dot Plot
••Histogram
Histogram
••Ogive
Ogive
The students of Mr. Enjoy class are expected to judge the use
of new teaching technique “CAT” by choosing :excellent,
above average, average, below average, or poor. The
following data show the answers of 20 different students in his
class.
Below Average
Average
Above Average
Below Average
Average
Above Average
Above Average
Above Average
Above Average
Above Average
Below Average
Below Average
Average
Poor
Poor
Relative
Percent
Rating
Frequency Frequency Frequency
Poor
2
.10
10
Below Average
3
.15
15
Average
5
.25
25
Average
5
.25
25
Above Average
9
.45
45
Excellent
1
.05
5
!
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Name
score
Name
acore
A
65
P
55
B
68
Q
70
C
70
R
65
D
85
S
80
E
90
T
95
F
87
U
70
!
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&
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%
&
%
F
87
U
70
G
95
V
85
H
76
W
85
I
70
X
80
J
90
Y
76
K
90
Z
60
L
80
A1
78
%
!'
"
• What is the median?
Name
score
Name
acore
A
65
P
55
B
68
Q
70
C
70
R
65
D
85
S
80
E
90
T
95
F
87
U
70
F
87
U
70
G
95
V
85
H
76
W
85
I
70
X
80
J
90
Y
76
K
90
Z
60
!'
"
Measurements x 3
%
&
Name
score
Name
acore
A
65
P
55
B
68
Q
70
C
70
R
65
D
85
S
80
E
90
T
95
F
87
U
70
3 5 5 1 7 2 6 7 0 4
F
87
U
70
G
95
V
85
H
76
W
85
I
70
X
80
J
90
Y
76
K
90
Z
60
)
,
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Measurements Deviations Square of
deviations
x x - mean
3 -1 1
5 1 1
-
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!
5 1 1
5 1 1
1 -3 9
7 3 9
2 -2 4
6 2 4
7 3 9
0 -4 16
4 0 0
!
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