#1

so i'm doing my stats homework and there are like 5 problems where i need to use a graphing calculator to find the standard deviation and the variance but i don't have one...are there any sites with a GC that can help me do that?

#2

They invented search engines, you know.

http://www.google.com/search?hl=en&q=graphing+calculator&btnG=Google+Search

http://www.google.com/search?hl=en&q=graphing+calculator&btnG=Google+Search

#3

They invented search engines, you know.

http://www.google.com/search?hl=en&q=graphing+calculator&btnG=Google+Search

if you would read my post you would see that i'm not looking for a calculator to graph, which is what your google search looked for...i need one that has the "stat" button or one that can help me find the standard deviation

*Last edited by blues-guitarist at Oct 7, 2007,*

#4

anyone?

#5

Sorry, you really need a calculator for that stuff.

#6

or you could do it the old fashioned way and work it out using all those gay formulas

i believe it was something like SD = square root of [(sum onf fx^2/ sum of FX)-(mean)^2)]

where fx^2 is the value of x^2 *

its been about a year since i did it last so it could be wrong lol

and the variance is just the same, but minus the square root

they other calculations can be done with any calculator

i believe it was something like SD = square root of [(sum onf fx^2/ sum of FX)-(mean)^2)]

where fx^2 is the value of x^2 *

its been about a year since i did it last so it could be wrong lol

and the variance is just the same, but minus the square root

they other calculations can be done with any calculator

#7

no, you dont need a calculator to do that. first you find the variance, and then you take the square root of the variance s=the square root of s^2. In order to find the variance, you do this

((sum of all the squared values) - ((sum of all the values)^2/number of values))

and all of that divided by the number of values minus 1

thats sounds screwed up i know but thats how you do it w/o a graphing calculator

_____________________________________________________

s^2= ((Ex^2)-((Ex)^2/n))/n-1

s=square root of s^2

or the standard devaiton equals the square root of the variance

thats it as a formula

((sum of all the squared values) - ((sum of all the values)^2/number of values))

and all of that divided by the number of values minus 1

thats sounds screwed up i know but thats how you do it w/o a graphing calculator

_____________________________________________________

s^2= ((Ex^2)-((Ex)^2/n))/n-1

s=square root of s^2

or the standard devaiton equals the square root of the variance

thats it as a formula

*Last edited by i bleed metal at Oct 7, 2007,*

#8

no, you dont need a calculator to do that. first you find the variance, and then you take the square root of the variance s=s^2. In order to find the variance, you do this

((sum of all the squared values) - ((sum of all the values)^2/number of values))

and all of that divided by the number of values minus 1

thats sounds screwed up i know but thats how you do it w/o a graphing calculator

cool..thanks

#9

I'm pretty sure they have emulators of some graphing calculators. Search it up yourself though, I'm a lazy bastard.

#10

cool..thanks

no problem

#11

doesnlt windows come with a scientific calculator, mine did, but I lost it

#12

just found a scientific calculator in my dad's room...any ideas how to find the deviation with a scientific one?

#13

I know there are graphing calc programs, but you have to buy them.

#14

anyone knows how to find the lower and upper quartiles or a sample without a GC?

#15

oh you mean a graphical calculator...

Go do it the old fashioned way!

Wikibooks probably have the way to work out the standard deviation algebraecly (sp?)

Upper quartile is the (3*number of values)/4 th value.

Lower is number of values/4 th value.

The set of data must be in ascending order.

Go do it the old fashioned way!

Wikibooks probably have the way to work out the standard deviation algebraecly (sp?)

Upper quartile is the (3*number of values)/4 th value.

Lower is number of values/4 th value.

The set of data must be in ascending order.

#16

^thanks

#17

first find the median ( middle number when all in numerical order) if it land on one exact, ignore that value for now.

now do the middle of each side, the side before is the lower quartile, the side above the upper quartile, simple really

now do the middle of each side, the side before is the lower quartile, the side above the upper quartile, simple really

#18

this is why you get a TI-83, their cheap too only about $115

#19

Dude, just go to Target or Wal-Mart spend $13 and get a TI-30, thats what me class uses.

#20

Dude, just go to Target or Wal-Mart spend $13 and get a TX-30, thats what me class uses.

i have that one...how do it use it?? i learned to do this stuff with TI-83s (graphing calc) so i have no idea how to do it with a tx 30

#21

There's no way you could go without a graphing calculator in a statistics class...

Or at least, not in AP statistics. =/

Or at least, not in AP statistics. =/

#22

There's no way you could go without a graphing calculator in a statistics class...

Or at least, not in AP statistics. =/

i'm in AP stas :S i guess i'm gonna have to buy one

#23

^ Without a doubt.

#24

I'm still using my TI-83 but my school upgraded and everyone bought TI-84 Silver Editions. They kind of suck because they freeze alot, my 83's always been reliable.

#25

I don't know what exactly you need, but this site is billed as a "Standard Deviation Calculator" on Wikipedia.

#26

I don't know what exactly you need, but this site is billed as a "Standard Deviation Calculator" on Wikipedia.

wow...this really helps, thanks