Maths questions

I haven't paid attention or really even showed up to my math classes in about a fortnight and now i have an assignment. I know most of the stuff and how to do it but there are a few things i need some help with.

These are some true or false questions i'm lost with.

1. The greater the standard deviation the greater the spread of scores?
2. The standard deviation can be larger than the range?
3. If the standard deviation is zero then all the scores are of equal value?


And i've kind of forgotten what X and Y are. I'm thinking that X is the vertical and Y is the horizontal but it's been ages since i've done a graph and i'm not sure.

X is horizontal. Y is vertical.

Got no clue on the other things.

Thanks. If no-one can answer those questions it'll be fine. I'll just randomly guess them since they aren't worth many marks. The rest of my work is correct so i'll still pass.

Quote :

1. The greater the standard deviation the greater the spread of scores?

The standard deviation of a set of data is the average distance each data point is away from the mean. If you have a huge spread of scores, you get a higher standard deviation. if you have little spread, you standard deviation becomes small. Answer is true/.

Quote :

2. The standard deviation can be larger than the range?

I'm not positive, but I'm pretty sure the answer is false. Unless I'm thinking of this wrong, but the range is your smallest value subtracted from your largest value. Let's take 5 and 1. Range would be 4. The average distance away from the mean can be no larger than 4. This should be false.

Quote :

3. If the standard deviation is zero then all the scores are of equal value?

True. There is no spread, therefore there is no standard deviation.

Thanks Cghost. I'm pretty bad at maths. I come top of the class in most of my other subjects but i have little time or enthusiasm for maths.

Anyone know what the interquartile range is?

I really need to stop skipping my maths classes but my teacher is so incompetent that i no longer see the point in showing up to class anymore.

My teacher last semester was terrible... She'd assign us the work, then the next day ask us if we knew how to do that.

Now... if you didn't catch that... She'd give us the work without telling how to do it. Then ask AFTER we got a grade for our homework if we knew how to do it.

I dropped that fucking class.

Our teacher gets us to read the work and he expects us to be able to solve things on our own without any assistance. Our last maths teacher was good but he got transferred. So now our class get pushed around to different teachers who have no fucking clue what they're on about. I'll probably just stop showing up to class full stop now and go and do something more creative with my time.

is this some sort of statistics course, or what?

I've taken a lot of maths in my day, and this is completely foreign... except the whole x- and y- axes on a quadratic plane....

i love math.

yes, i am a freak.

I do general maths so we learn about a whole bunch of shit i have no interest in.

wow...

i love algebra... so i'd be good for that.

calculus, so-so... business calculus, i loved.

etc.

yes, i'm still a freak.

Chadwick likes calculus.

well, as he proclaims quite often in some form or another, he's just awesome

Green_shoes wrote:

Anyone know what the interquartile range is?

I really need to stop skipping my maths classes but my teacher is so incompetent that i no longer see the point in showing up to class anymore.

IQR is all the data in between the 25th and 75th percentile, so to find it you subtract the 25th percentile from the 75th.

edit: wtf is a quadratic plane? did you mean cartesian?

hot damn.

it won't help anyone's opinions of Mississippi, but i swear we don't even have the same math.

This is stats.

So you just divide your score of numbers up in to three even sections?
What if you have an odd score of numbers?
and
What number do you minus, do you minus all the numbers combined in the 1st and 3rd percentile or do you minus the lowest number in the 1st percentile from the largest number in the 3rd percentile.

Green_shoes wrote:

So you just divide your score of numbers up in to three even sections?
What if you have an odd score of numbers?
and
What number do you minus, do you minus all the numbers combined in the 1st and 3rd percentile or do you minus the lowest number in the 1st percentile from the largest number in the 3rd percentile.

what in the fuck are you talking about?

Find the 25th percentile. Find the 75th percentile. Subtract the 25th from the 75th. What's this dividing jargon?

okay. that makes me feel better that this is statistics... i've not taken a course in it...

thought MS once again sucked and was way behind

How ignorant I feel now....

lol i have no idea. My maths teacher teaches us shit all so i've been trying to teach myself but i suck at maths. I hate numbers, i'm more or a man of words.

IAmHeavenSent wrote:

okay. that makes me feel better that this is statistics... i've not taken a course in it...

thought MS once again sucked and was way behind

They are. YOu never answered my question. Quadratic plane? did you mean Cartesian?

Green_shoes wrote:

lol i have no idea. My maths teacher teaches us shit all so i've been trying to teach myself but i suck at maths. I hate numbers, i'm more or a man of words.

Just find the 25th and 75th percentiles and subtract them. I can't off the top of my head remember how to do that. I think you multiply the mean by .25 and by .75 and then always round up. My stats prof showed us a different way of doing it then it said in the text book though, so I can't even remember if that's correct.

my bad--didn't see the edit...

i'm sure that is... i couldn't remember what my teachers had called it... i'm almost positive they didn't call it cartesian, but i wasn't sure if it was quadratic....

Quadratic plane is just when talking about the 4 quadrants of a grid, right?