stdevp( ) appears to be mislabeled

[Mike Elzinga]

(06-05-2016 05:34 PM)Wes Loewer Wrote:  

(06-05-2016 06:35 AM)parisse Wrote:  I don't understand why someone would say standard deviation of population from population.

Agreed. I just wanted to make sure I correctly understood. I guess I've never seen the expression "standard deviation of the population based on a sample." The "of the population" is usually implied, so I wanted to make sure I wasn't misunderstanding anything. In American texts, it's usually referred to as the "standard deviation of a sample" or just "sample standard deviation".

Quote:Excel and other spreadsheets may have different views, they are not math softwares, people using them are not expected to understand what standard deviation is.

I suspect that other products like the 50g and Excel chose the shorter name for the sample version since that is the one that is more commonly needed. In fact, on the TI-84+ and 89, there is not even a stand alone function for the population standard deviation, only the sample standard deviation, stdDev().

In any case, removing ambiguity is always a good idea. No one could possibly be confused by names like stddev_samp and stddev_pop.

I have a TI-89 Titanium; and I just checked.

The TI-89 has stdDev (division by N-1) and stDevPop (division by N).

Excel 2016 has several forms of standard deviation; including STDEV.S and STDEV.P

The statistics package on Excel is fairly good.