TECHNICAL ANNEX

Introduction

This annex describes the methods that have been used to calculate the KS2 to GCSE/GNVQ, the historical KS2 to KS3 and the KS3 to GCSE/GNVQ value added measures.

The annex is split into seven sections:

• Allocation of point scores to results
• Calculation of the input and output measures used in the value added calculations
• Pupils included in the value added calculations
• Calculation of the KS2 to GCSE/GNVQ value added measures
• Calculation of the historical KS2 to KS3 value added measures
• Calculation of KS3 to GCSE/GNVQ value added measures
• Length of time in current school

Allocation of points

The `input' and `output' measures for the value added calculations are based on the points awarded to pupils' results. The following tables show how points are allocated to pupils' KS2, KS3 and GCSE/GNVQ results.

KS2 Point Scores for all subjects

KS3 Point scores

GCSE/GNVQ Point Scores for all subjects

Calculation of input and output measures

Three measures must be calculated for pupils in order that the three value added scores may be calculated;

KS2 Average Point Score

The input measure for each pupil's KS2-GCSE/GNVQ and historical KS2-KS3 value added score is calculated as the average (arithmetic mean) point score achieved in the English, maths and science tests at KS2, using the points allocated to each level as described earlier.

Please see example below

Example 1:

If any KS2 results for a pupil are disregarded, the input measure is calculated as the average of the remaining non-disregarded subjects.

KS3 Average Point Score

The input measure for each pupil's KS3-GCSE/GNVQ value added score is calculated as the average (arithmetic mean) point score achieved in the English, maths and science tests at KS3, again using the points allocated to each level as described earlier and using the same method as that used to calculate the KS2 average point score.

The KS3 average point score is also used as the output measure in the historical KS2-KS3 value added calculation.

GCSE/GNVQ Capped Point Score

The output measure for each pupil's KS2 to GCSE/GNVQ and KS3 to GCSE/GNVQ value added score is a capped point score achieved at GCSE/GNVQ. This is calculated as the best 8 GCSE or GNVQ equivalent results, using the points allocated to each grade as described earlier.

In order to calculate the capped GCSE/GNVQ point score for each pupil, each qualification has been divided into records to show its equivalence to the smallest qualification, which is a GCSE (Short Course) and has half the weight of a full GCSE as shown below:

In effect we are thus capping at the best 16 GCSE short course equivalents.

The point score allocated to each result is also divided by the number of records. For example, a pupil who achieved 3 Bs and 2 Cs at GCSE, an A* for a GCSE (Short Course) and a full Intermediate GNVQ with distinction would have their results broken down and their capped GCSE/GNVQ point score calculated in the following way:

Only the 16 highest scoring records (i.e. the best 8 GCSE/GNVQs) are used to calculate a pupil's point score. In this case the lowest five records worth 2.5 points each and representative of two and a half GCSEs at grade C are disregarded. In this example the pupil's point score is 54.5

The average capped point score per pupil for a school is calculated by dividing the overall number of points (capped as described above) by the number of pupils.

Pupils included in the value added measures

The value added measures are based on the results achieved by pupils:

• who were aged 15 on 31st August 2002; and
• for whom we have been able to match prior attainment in the relevant Key Stage tests.

All pupils for whom all results are disregarded at KS2 have been excluded from the historical KS2-KS3 and KS2-GCSE/GNVQ value added calculations, with one exception: if a pupil is disapplied in at least one subject and achieved at least one result at KS3 or GCSE/GNVQ respectively which was not disregarded, then he/she will be included in the calculation with an input score of zero. The same principles have been applied to pupils with all KS3 results disregarded for the KS3-GCSE/GNVQ value added calculations.

Key Stage 2 to GCSE/GNVQ value added measure

Calculation of a pupil's KS2 - GCSE/GNVQ VA measure

The pupil's value added score is based on comparing their GCSE/GNVQ performance with the median GCSE/GNVQ performance of other pupils with the same or similar prior attainment at KS2. The median value is the middle value - with half of the pupils having a total GCSE/GNVQ point score at or below the median, and half at or above.

The graphs below give the pattern of median GCSE/GNVQ point scores across the range of KS2 point scores nationally - joining the medians gives the 'national median line'. There are two graphs: one shows median scores for mainstream schools and the other shows median scores for pupils in special schools only.

The median capped GCSE/GNVQ point scores are also given in the tables below:

Mainstream Schools

Special Schools

Calculation and presentation of a school's KS2 - GCSE/GNVQ VA Measure

In the example below, school A, a mainstream school, has 5 pupils eligible for inclusion in the KS2 - GCSE/GNVQ VA measure with average KS2 and capped GCSE/GNVQ point scores shown below. Median capped GCSE/GNVQ point scores have been allocated according to the national median line for mainstream schools shown above, and a VA score calculated for each pupil.

A school's VA score is a simple average (arithmetic mean) of the VA scores for all the pupils in the school eligible for inclusion in the VA measure. Therefore, the VA score for school A is:

Note: All figures will be rounded to 1 decimal place using normal rounding conventions.

The value added measure (KS2 to GCSE/GNVQ)

The value added score for each school has been published in terms of a measure centred around 100 - i.e. by adding 100 to a school's value added score. In the example above the value added measure for school A is:

= 0.4 + 100 = 100.4

= 100.4 (rounded to one decimal place using normal rounding conventions)

Calculation of the school's coverage indicator

This shows the percentage of pupils included in the school's number of 15 year olds on roll figure who were included in the value added measure for that school.

For example, if a school had 30 15 year olds on roll in 2003 but only 25 were included in the value added calculations, the coverage indicator for that school would be:

(25 / 30) x 100 = 83%

Average number of GCSE/GNVQs taken by pupils in the value added calculation

This shows the average number of GCSE/GNVQs taken by each pupil included in the value added calculation. It has been calculated by dividing the total number of GCSE/GNVQ examinations taken by each pupil by the number of pupils included in the calculation. The total number of examinations has been determined using the table of GCSE and GNVQ equivalencies set out in the first part of this annex.

For example, a school has ten pupils who are included in the calculation and the number of GCSE/GNVQs taken by each of the pupils is as follows:

The calculation in this example for the average number of GCSE/GNVQs taken by pupils would be:

(8 + 10 + 6 + 8 + 8.5 + 8 + 10 + 9.5 + 4.5) / 9 = 8.056

This would be rounded to 8.1 using normal rounding conventions.

Historical Key Stage 2 to Key Stage 3 value added measure

Calculation of historical KS2 - KS3 VA measures and associated figures

The historical KS2 to KS3 value added measures, and coverage indicators are calculated using the method outlined above for the KS2 to GCSE/GNVQ measures.

The graphs below give the pattern of median KS3 average point scores across the range of KS2 average point scores nationally - joining the medians gives the 'national median line'. There are two graphs: one shows median scores for mainstream schools and the other shows median scores for pupils in special schools only.

The median average KS3 point scores are also given in the tables below:

Mainstream schools

Special Schools

Key Stage 3 to GCSE/GNVQ value added measure

Calculation of KS3 - GCSE/GNVQ VA measures and associated figures

The KS3 to GCSE/GNVQ value added scores at both pupil and school level as well as the value added measures and coverage indicators are calculated in exactly the same way as outlined above for the KS2 to GCSE/GNVQ measures.

The graphs below give the pattern of median capped GCSE/GNVQ point scores across the range of KS3 average point scores nationally - joining the medians gives the 'national median line'. There are two graphs: one shows median scores for mainstream schools and the other shows median scores for pupils in special schools only.

The median average KS3 point scores are also given in the tables below:

Mainstream schools

Special Schools

The stability indicator

One additional indicator is calculated for the KS3 to GCSE/GNVQ value added measure. This is called a stability indicator and shows the percentage of pupils included in the value added calculation who took both their KS3 tests and GCSE/GNVQs in the same school. For example, if a school has 10 pupils in the value added calculation and only 7 took both their KS3 tests and GCSE/GNVQ examinations in the same school, then the stability indicator would be:

(7 / 10) x 100 = 70%

Length of time in current school

Two additional indicators have been calculated as part of the 2003 pilot work. These give the percentage of 15 year old pupils on roll who have been in the school for 2 or more years and for 5 or more years.

The indicators are calculated using the pupil date of entry included in schools' Pupil Level Annual School Census (PLASC) returns. As a result it has only been possible to calculate these indicators for schools who have completed PLASC returns.

The figure is calculated by first computing, for each pupil, the number of years that the pupil has spent in the school where they are currently on roll. If the pupil start date is prior to 1st October in any given school year, then the pupil is considered to have been in the school for the entire school year. Pupils starting school on or after 1st October are not considered to have been in the school for the whole year.

The indicators are calculated by summing the number of pupils in the school for 2 years or more, or 5 years or more respectively, then dividing this by the number of 15 year old pupils on roll.

Example:

If a school has 46 pupils and 35 of these have been in the school for 5 years or more, the 5 year PLASC mobility indicator for the school will be

(35 / 46) x 100 =76.09%

This will be rounded to the nearest whole number, using normal rounding conventions and so will be published as 76%.

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