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OUTLINE

• PSLE is a placement exam

• What is the PSLE Aggregate SCORE?

• Why is T-Score used?

• Definition & Calculation of T-Score

• Questions about T-Score

PSLE - a placement exam

• Need to reflect the relative achievement level of pupils within their 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 their choice.

What is PSLE Aggregate Score?

It is a sum of scores.

What are these scores? Are they

raw scores?

The PSLE Aggregate Score

• incorporates performance of pupils in all 4 subjects

• allows pupils to be ranked fairly

Can raw scores be used?

NO !

Why Not?

• 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)

MEASURE OF S P R E A D

Narrow Wide

DOLLY

I scored 85% in both English and Mother

Tongue !

H U R R A Y !

Dolly scores 85% in both EL and MT

85%

EL

EL ave = 60

MT

MT ave = 80

Her performance in MT is very close to that of other pupils

She did much better in EL as compared to other pupils

0 100

A need for standardisation of the raw scores

Transformed Score or T-Score

T-Score

ave = 60

EL MT

ave = 80

50

85% 85%

T-Score converts average mark of each subject to a common score of 50 points. It also converts other marks taking into consideration the extent to which they differ from the average and the size of spread of the marks around the average

What is 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 compared to others

How is T-Score calculated for each subject?

where X: pupil’s mark for the subjectY: average mark (mean) scored by all pupilsZ: spread of marks around the average mark (standard deviation)

ZY)-(X10 50 T

Example:

• Pupil’s mark (X) in exam = 50.0• Average mark (Y) scored by

all pupils = 68.0• Spread of marks (Z) around the

average mark (Y) = 14.0

T = 50 + 10 (50 - 68.0)14.0

= 37.14

How is the AggregateScore calculated?

By adding the T-Scores ofthe 4 subjects

Example:

Subject Total Mark T-ScoreEL1 200 105 34CL2 200 152 51

Maths 100 67 53Science 100 58 47

Aggregate: 185

Finally,

all pupils are ranked according to their Aggregate Scores

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

John’s Susan’sSubj

Mark(Grade)

T-Score

Mark(Grade)

T-Score

EL1 182A

60 190A*

68

MT 185A*

70 180A

68

MA 91A*

60 80A

58

SC 92A*

56 86A

55

Aggregate T-Score: 246 249