2. OUTLINE
• PSLE is a placement exam
• What is the PSLE Aggregate SCORE?
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• Why is T-Score used?
• Definition & Calculation of T-Score
• Questions about T-Score

3. PSLE - a placement exam
• Need to reflect the relative
achievement level of pupils within their
peers.
peers
• Places pupils into different courses
according to their academic ability
• Enables posting to secondary schools
by merit and as far as possible into a
school of th i choice.
h l f their h i

4. What is PSLE Aggregate Score?
It is a sum of scores.
What are these
scores? Are they
raw
scores?

5. The PSLE Aggregate Score
• incorporates performance
of pupils in all 4 subjects
• allows pupils to be ranked
fairly
y

6. Can raw scores be used?
NO !

7. Wh Not?
Why
• Different subjects have different
levels of difficulty
• So are the spread of marks from
the average mark, i.e. the
standard deviation
(spread = standard deviation)

8. MEASURE OF
S P R E A D
Narrow Wide

9. HURRAY!
I scored 85% in
both English
DOLLY and Mother
Tongue !

10. Dolly scores 85% in both EL and MT
Her performance in MT is very
close to that of other pupils
p p 85%
She did much better
in EL as compared to
other pupils
EL
MT
0 100
EL ave MT ave
= 60 = 80

11. A need for standardisation of
the raw scores
Transformed Score
or T-Score

12. EL T-Score
MT
85% 85%
ave = 80
ave = 60
50
T-Score converts average mark of each subject
to a common score of 50 points It also converts
points.
other marks taking into consideration the extent
to which they differ from the average and the
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size of spread of the marks around the average

13. What is T-Score?
T Score?
• It gives the relative position of a
pupil’s performance as compared
to the performance of all the other
pupils in that subject
• The raw mark obtained in the exam
only shows how good the pupil is in
that subject, not how good he is as
subject
compared to others

14. How is T-Score calculated for
each subject?
T = 50 + 10 (X - Y)
Z
where
X: pupil s mark for the subject
pupil’s
Y: average mark (mean) scored by all
p p
pupils
Z: spread of marks around the average
mark (standard deviation)

15. Example:
p
• Pupil’s mark (X) in exam
p ( ) = 50.0
• Average mark (Y) scored by
all pupils = 68.0
• S
Spread of marks (Z) around the
d f k d th
average mark (Y) = 14.0
T = 50 + 10 (50 - 68.0)
14.0
= 37.14

16. How is the Aggregate
Score calculated?
By adding the T-Scores of
the 4 subjects

17. Example:
a pe
Subject Total Mark T Score
T-Score
EL1 200 105 34
CL2 200 152 51
Maths 100 67 53
Science 100 58 47
Aggregate: 185

18. Finally,
Finally
all pupils are ranked
according to their Aggregate
Scores

19. T-SCORES & GRADES:
Is it possible for a pupil with
3A* and 1A to be ranked lower
than another pupil who has
only 1A* and 3As?
Yes, it is possible

20. Subj John’s Susan’s
Mark T- Mark T-
(Grade) Score (Grade) Score
EL1 182 60 190 68
A A*
MT 185 70 180 68
A* A
MA 91 60 80 58
A* A
SC 92 56 86 55
A* A
Aggregate T Score:
T-Score: 246 249