Question about Texas Instruments BA-II Plus Calculator

# Getting Weighted Std Dev for probability.. - Texas Instruments BA-II Plus Calculator

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Sorry, boss.

But getting standard deviation from a probability distribution would probably be best done by hand (of course, with the use of a computational device for those hard-to-reach fractions).

If your distribution question has a long line of events (IE, data points) then you'd probably want to use a more advanced calculator.

Nevertheless....I will return this afternoon with a more informed answer after I tinker with my BA-II Plus.

Whenever I do these, though, I usually pop open my TI89 Titanium (or of course just do it by hand).

STAY TUNED, MO...

Posted on Mar 12, 2011

• Math Cheetah Mar 13, 2011

MO MO....

I just finished messing around with the good old BA II Plus and this is what I've found:

GOOD NEWS:
You CAN find an unweighted mean & standard deviation.

You CANNOT find a weighted standard deviation.

SORRY; judging by your question it seems as if you may have already come to this conclusion. The statistics menu on the BA II Plus just doesn't go into detail for a random variable like that.

However, you CAN use a TI Graphing Calculator to set up a few lists which will aide in discovering the standard deviation of a discrete random variable.

PEACE.

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Posted on Jan 02, 2017

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In the case of hard drives, there is another abstraction. A hard drive (and many devices such as USB "sticks" which act like hard drives) can be partitioned to allow many filesystems to be stored on them. This means that the filesystems themselves are accessible via the partition labels, such as /dev/hda1 (the first partition on /dev/hda). This means that we finally know about something we can mount, a partition, since it contains a filesystem.

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Floppy disks only contain one filesystem, and are labeled as /dev/fd0 for the first drive, /dev/fd1 for the second drive, etc. So now we know three things which can be mounted.

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