Help needed to understand Standardised scores for Non Verbal Reasoning and maths 11 plus

(13 Posts)
PrivatelyPeaceful Tue 05-Feb-13 15:49:13

Hi,
My dd is 10y10 months and has just been accepted at a (not very selective) independent secondary.

They do an 11+ style exam.

DD did a few practice papers for 1 week to ten days before the exam.

I am now trying to get a sense of her level and what her scores mean.

DD got 121 for NVR but only 93 for maths. (they state that normal range is a SS of 85-115 for maths and NVR.) we know that her maths is her weakest subject, but just wondered if this suggests that she is underachieving in maths. Does it follow that if your NVR score is ok, then you should be performing better at maths?

the school said that her NVR score suggests potential. are they just being kind, or is that an ok ish score for an untutored child?

tia for any advice

JoanByers Wed 06-Feb-13 02:39:36

Generally speaking 100 is given as the mean on standardised tests, and the standard deviation is 15.

The normal distribution, or bell curve, describes many distributions, e.g., test scores, the number of hours a light bulb lasts, etc.

For the normal distribution approximately 34.1% of results will be between 0 and 1 standard deviations less than the mean (85 to 100), and 34.1% of results will be between 0 and 1 standard deviations above the mean (100 to 115).

And of course exactly half of scores will be above 100 and half below 100.

This graph shows the general distribution of normally distributed data:

www.mathsisfun.com/data/images/normal-distrubution-large.gif

As you can see, a score of 93, which is half a standard deviation below the mean, is around about the 30th percentile, so if you picked 10 children at random, 7 would have scored better on that test, and 3 would score at or below her level.

As for the non-verbal reasoning, this is highly correlated with the quantitative ability score, and a score of 121 is roughly 1.5 S.D.s above the mean, so this around the 92nd percentile, so only one child in twelve is expected to score better than this.

If your child has never done an NVR test before, then 121 suggests that she is very bright. If she has done any amount of practice, then my opinion is that the score is inflated, since you can coach for NVR quite effectively, however 121 is still a score that would tend to imply a higher score on the quantitative test.

It's worth noting that the 93 is NOT maths, but quantitative reasoning, which is designed to measure the ability to do maths, rather than any specific maths knowledge (more selective independent schools would tend to set an actual maths test, whereas it sounds like this school has done CAT scoring in order to understand where she fits in).

There's some info on the tests here:

gla.gl-education.com/sites/gl/files/images/Files/GLA510%20-%20CAT4%20Assessment%20Overview.pdf

See also:

www.nfer.ac.uk/nfer/research/assessment/eleven-plus/standardised-scores.cfm
www.gl-assessment.co.uk/sites/gl/files/images/Files/CAT_Primary_SR_20pp.pdf

This file shows correlation between CAT scores and GCSE results:

www.gl-assessment.co.uk/sites/gl/files/images/Files/GCSE_Technical_Information.pdf

Maths GCSE is most highly correlated with the mean CAT score (quantitative, VR and non-VR together), and both non-VR and quantitative scores are highly correlated with performance here, with a slightly, but not hugely, higher correlation to quantitative. A mean score of 105-110 (you don't mention VR score?), indicates that the most likely grade at GCSE would be a B.

So there is nothing particular to worry about IMO, even though she has an unusually spiky profile - it does look as if perhaps she has something of a mental block when it comes to numbers, even though she is generally good at non-VR/logic/maths-type stuff.

If you are specifically concerned about her maths, I suggest you check her KS2 maths SAT score. Past papers are available online, and it's very easy to mark.

PrivatelyPeaceful Wed 06-Feb-13 18:09:41

Joan, what an informative and helpful post. Thanks so much for going to such trouble to post.

I am pretty sure it was an actual 'maths' test based on what we were told/ what dd said.

Re NVR practice, we only found out a week before that this was part of the exam! She did 3 ten minute Bond practise tests during that time. Her dad and I
Talked her through the idea of spotting A pattern but she worked mostly alone.

She got 103 for English (normal range 88 to 112) and 105 for VR ( normal range 85 to 115) . How do I work out which centile that equates to??

Tia smile

PrivatelyPeaceful Wed 06-Feb-13 18:11:52

Sorry about awful paragraphing/ punctuation. Damned iPad!

JoanByers Wed 06-Feb-13 18:24:53

You can do it in Excel =norm.dist(<score>,<mean>,<standard deviation>,true)

I.e. =norm.dist(103,100,12,true) and =norm.dist(105,100,15,true)

Seems like the non-VR is the outlier.

PrivatelyPeaceful Wed 06-Feb-13 19:16:04

Joan, thanks but I'm not clever enough to interpret your last post smile

JoanByers Wed 06-Feb-13 19:18:41

do you have Excel? (other spreadsheet products are available)

If you paste

=norm.dist(105,100,15,true)

into a cell there, it will give you the answer.

Copthallresident Wed 06-Feb-13 20:47:13

PrivatelyPeaceful Most schools will test for Specific Learning Difficulties very early in Year 7 (sometimes known as the Durham tests), alongside providing them with a baseline for achievement. That should pick up whether the disparity is to do with a learning difficulty or some other explanation (teaching, poor performance on the day). It may be something to keep an eye on.

PrivatelyPeaceful Thu 07-Feb-13 09:37:04

Thanks, the more I think about it, I think she is underachieving in maths. The things I have revised with her reveal some big gaps but also an aptitude to learn.

I think her errors and the strategies that she uses show potential with gaps in teaching.

Eg 1 she couldn't remember many formal methods for written calculation so was relying on a complex process of jottings/ mental calculations. 2 She was not secure with place value with decimals but fantastic with place value of 6 digit numbers. when taught by me, she grasped decimals very quickly. 3 She wasn't sure how to compare / find the smallest fraction in a set so was trying to use a process of visualising how big the fraction was, and eliminating each possibility. She had not been taught to convert fractions by using common denominators or any other reliable method. 4. Loads of gaps in other areas eg area, perimeter, co ordinates! Basic stuff that she picked up in a flash. I have worked everyday with her for 2 weeks doing a little maths with her. She has told me that she is understanding her class maths much better and has more confidence. She has asked me to carry on helping her with her maths. I am shocked that 2 weeks has made such a difference to her confidence and think that it points towards poor teaching( in part).

She was 2a in maths at the end of year 2. She started a new school at the end of year 3, where they set for maths. She spent over a year at the very top of the lower of two sets. She was forever saying that 'she used to be good at maths at her old school'. I think she was labelled as not being good at maths, and her confidence took a nose dive.

Btw re the 'maths test' I know she had to do things like find missing angles in a triangle, round decimals, solve division problems. So... It wasn't a maths reasoning paper. It's the reasoning bit that she can do- am convinced!

Am feeling quite sad about this actually. She was a 2a in year 2 and now in year 6 is on 30th centile. And she is clearly bright.

IDK Thu 07-Feb-13 10:19:01

Most schools will test for Specific Learning Difficulties very early in Year 7 (sometimes known as the Durham tests)

Can you elaborate please? I'm sure that DS's entrance tests were Durham but the school never picked up on his Specific Learning Difficulties. Are they different tests?

Copthallresident Thu 07-Feb-13 11:35:31

IDK I don't know if an entrance test using tests developed by Durham would be the same as the ones a lot of schools use to establish a baseline early on and attempt to pick up learning difficulties. My DDs sat the school's own entrance exam and then these tests subsequently, and actually they didn't pick up DD1s Dyslexia definitively but they did arouse her English teacher's suspicions which she acted on a year or so later. However for OP it is a possible opportunity to raise the issue with the school, and to make sure no one takes their eye of the ball.

Inaflap Thu 07-Feb-13 16:18:06

There are all sorts of tests to pick up specific difficulties. One of te things looked at would be a mismatch of a high NV reasoning and low average scores (in the low 90 or high 80) in maths or literacy. Schools use a range of tests now but the best thing is watching and waiting and listening to staff. Things usually start cropping up around now in the year when the fulll measure is got and te honeymoon period is over. Original OP those scores are fine but maths is a bit lower than average so she perhaps needs a boost there.

PrivatelyPeaceful Thu 07-Feb-13 16:24:56

Thanks (smile)
I do really think though, that it's more due to her learning experiences at school than being inherently poor at maths (see my post from 9:37am).

Join the discussion

Join the discussion

Registering is free, easy, and means you can join in the discussion, get discounts, win prizes and lots more.

Register now