VCE General & Further Maths Question Thread!

[bellaellaella]

Is the height of something considered to be numerical or categorical data?

[Sense]

Is the height of something considered to be numerical or categorical data?

Most likely numerical. It could be categorical if it was short, normal and tall or something but most of the time it's in cm

[bellaellaella]

Most likely numerical. It could be categorical if it was short, normal and tall or something but most of the time it's in cm

So if it's in cms it's discrete numerical data?

[Sense]

Nah, continuous. Cm don't have to be a whole number they could be 178.8586589754798548

[bellaellaella]

Nah, continuous. Cm doesn't have to be a whole number it could be 178.8586589754798548

What if we're given values that do not have decimals?
My teacher said that shoe size is categorical data so now I'm just so confused

[Sense]

I'm pretty sure if it's cm it will still be continuous even if they only have whole numbers

Yeah, a lot of teachers say different answers for shoe size, but it can be either, large medium small or in numbers. If they don't state which one it is in the question then they are wrong.

[bellaellaella]

I'm pretty sure if it's cm it will still be continuous even if they only have whole numbers

Yeah, a lot of teachers say different answers for shoe size, but it can be either, large medium small or in numbers. If they don't state which one it is in the question then they are wrong.

And I thought further would be my easiest subject....boy was I wrong

[Zealous]

And I thought further would be my easiest subject....boy was I wrong

Discrete:
If we're given shoe sizes like 6, 6.5, 7, 7.5, 8, 8.5, 9 and so on... This is discrete data as our shoe sizes can only take these values (they cannot be in between).

All of the data in this table here is discrete: http://www.zangle.com.au/wp-content/uploads/2012/05/womanssizeshoes3.png (some quick googling)

Continuous:
If we were to measure our shoes to see their physical length in centimetres, this would be continuous. My shoe is not going to be 22.51cm, but rather 22.516367219cm... and so on in decimal places. The number of decimal places is limited by our recording equipment, what we use to measure the length.

Categorical vs Numerical:
The two examples above are numerical pieces of data. As Sense was saying before, if we expressed our shoe size as not a number but as a category (such as small, medium, large, extra large) ...  then we'd have categorical data.

Hopefully that helps clear some things up.

[Yacoubb]

And I thought further would be my easiest subject....boy was I wrong

Don't worry! I think every Further student starts off thinking they're going to score 40+ with little difficulty. Most learn that this is not the case. Further is about perfection - if you don't perfect your work for Further, and minimise your errors, scoring high is not really possible. Good luck to you all though - just remember not to underestimate this subject.

[bellaellaella]

Don't worry! I think every Further student starts off thinking they're going to score 40+ with little difficulty. Most learn that this is not the case. Further is about perfection - if you don't perfect your work for Further, and minimise your errors, scoring high is not really possible. Good luck to you all though - just remember not to underestimate this subject.

That's exactly why I'm trying to get my head around it while it's still relatively early days

[Einstein]

That's exactly why I'm trying to get my head around it while it's still relatively early days

Don't worry! I think every Further student starts off thinking they're going to score 40+ with little difficulty. Most learn that this is not the case. Further is about perfection - if you don't perfect your work for Further, and minimise your errors, scoring high is not really possible. Good luck to you all though - just remember not to underestimate this subject.

exactly the same here, all those little tricks

[That_Guy18]

Hi guys. This is my first ever post here so, I'm kinda new.
I've recently been given a practice sac from my teacher and I'm stuck on a question that requires us to comment on the shape, centre and spread of a boxplot. If someone could detail what needs to be said in each of those three it'd be much appreciated. Thank you.

[bellaellaella]

Hi guys. This is my first ever post here so, I'm kinda new.
I've recently been given a practice sac from my teacher and I'm stuck on a question that requires us to comment on the shape, centre and spread of a boxplot. If someone could detail what needs to be said in each of those three it'd be much appreciated. Thank you.

I'm pretty sure the shape is about the distribution/skew (normally distributed, positive of negative skew), the centre is the median and spread should be range (highest minus lowest value)
Maybe wait for someone else to post but that's how I've been doing it.

What textbook are you using?

[~V]

I forgot my bound book at school! Basically,I had a little guide as to how to comment. Yeah, shape is about skewedness but remember the centre is median. Spread could be range, iqr, or standard deviation. There was a really good post by yacoubb on another thread about this and his way is really detailed and should ensure you get full marks.
Link here: Describing a Histogram's SHAPE, CENTRE, SPREAD

[That_Guy18]

bellabella, I'm using Maths Quest 12, 4th Edition
~v, thanks a lot for the link, it really helped