Looking to buy a calculator.

[chubber8]

I'm looking for any recommendations for calcs that I could use for probability calculations (factorials, standard deviation, etc).

If you could provide the model number, and other similar model numbers I would greatly appreciate it.

My limit is about $50 CDN for this.

Thanks.

[jimmyfingers]

when you say standard deviation you mean you want to input the data set and it calculates the sd for you?

i've used lots of calculators for probability but never needed that functionality, sorry

[chubber8]

Yes. I've seen a few models capable of calculating standard deviation, but none that I liked that were under $100.

What model calcs have you preferred (for ease of use, screen size, or any reason) for probability?

[uDevil]

The RPN HP 32SII was pretty nice. However, it's been replaced by the HP 33, which has RPN and algebraic modes. You should be able to get it for ~$40.

[BruceZ]

[ QUOTE ]
Yes. I've seen a few models capable of calculating standard deviation, but none that I liked that were under $100.

What model calcs have you preferred (for ease of use, screen size, or any reason) for probability?

[/ QUOTE ]

This HP 12C financial calculator can do it for $50, and here is the more advanced HP 12C Platinum 25th Anniversary Edition for more money. I believe these both have a factorial, but apparently not C(n,k) and P(n,k), though you could easily program those functions. These financial calculators are cousins of the now highly sought after HP 15C scientific calculator which I own, and this does do C(n,k) and P(n,k) along with the statistical functions. Many people, including myself, consider this to be the best scientific calculator ever made.

Two of the reasons for this preference are the fact that they are RPN (reverse polish notation, no need for equal sign or parentheses), and that they have a landscape key layout rather than portrait, and these features are shared with the HP 12C, though the platinum edition can apparently handle either RPN or algebraic input. These same features are also the reason that the HP 15C was discontinued since they are not what most people are used to. They try to hold the calculator in one hand and push the buttons with the other, but what you have to do is hold it with both hands and use both thumbs to hit the keys, and once you are used to this, it is very natural and efficient. Once you take a little time to get used to RPN, you will be able to enter expressions with fewer keystrokes, and with far less chance of making an error on complicated expressions since you enter them from inside out, rather than having to keep track of parentheses.

[pzhon]

Just about any scientific calculator will have a factorial button. You should be able to find a TI-30 for under US$20, but you can also use Google: 11!/8! 20 choose 6 or one of the many web scientific calculators.

However, a spreadsheet is a better choice for manipulating lists or arrays of data. In both Excel and Google Spreadsheet, you can use STDEVP() to compute the standard deviation of a collection of cells.

[_TKO_]

Sharp EL-510R ~$10

I don't know how to use all the functions, but there appears to be support for stats.

[alThor]

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Sharp EL-510R ~$10

[/ QUOTE ]

My EL-506A is just about to turn 20 years old. I think I paid about $10 for it. Still works. And as tedious as it is, you can enter data to calculate things like "s", etc.

I would never spend more than this on a calculator nowadays, when you can always turn to a computer for serious work.

[southerndog]

Ti 83

[Ampelmann]

Are you sure you need a stand alone calculator? Maybe a computer program that can calculate all this (and more) is sufficient?

In this case I'd recommend Octave. It's completely free (GPL).