NORMALD_ICDF (LEFT/CENTER/RIGHT)

[Wes Loewer]

(02-20-2020 09:03 PM)StephanP Wrote:  Of course there are ways to work around this, but my colleagues and I kind'a like this from the otherwise quite backward TI-84 Plus CE-T.

Could the function NORMALD_ICDF() be enhanced with an additional optional argument LEFT/CENTER/RIGHT indicating the position of area p?
If not supplied, then option LEFT is assumed standard.

NORMALD_ICDF(185,10,.85,RIGHT)=NORMALD_ICDF(185,10,1-0.85)=174.635...
NORMALD_ICDF(185,10,.85,CENTER)={170.604...; 199.395...}

I agree. My stats students with the TI-84 Plus CE really like this feature. It would be a very welcomed addition to the Prime. In fact, besides adding RIGHT to complement LEFT, I would also add OUTSIDE (or maybe TAILS) to complement CENTER.

Unfortunately, the TI-84 Plus CE only has this feature for the inverse Normal function. Why not include it in the inverse T, Chi Square, and F distributions as well?