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When entering 2 variable statistics on my WP 34S, when selecting X-bar, I get X-bar and Y-bar (means) in the X and Y stack display. If I enter a value into the command line, I can easily get the normal distribution results...the "X" values are assumed. Is there a way to swap X and y values for my 2 variable stats to compute normal distribution values for y values?
(05-04-2017 04:26 PM)lrdheat Wrote: [ -> ]When entering 2 variable statistics on my WP 34S, when selecting X-bar, I get X-bar and Y-bar (means) in the X and Y stack display. If I enter a value into the command line, I can easily get the normal distribution results...the "X" values are assumed. Is there a way to swap X and y values for my 2 variable stats to compute normal distribution values for y values?

I am not sure if I understand your problem. Could you provide an example? What exactly do you enter and what "normal distribution results" do you expect to get?

Dieter
I enter an X value, then a y value, and hit the summation key, and do so for my list of X and y values. If I then execute X-bar (mean X), X-bar AND y-bar are placed in the X and y display lines. If I enter some number into the command line, go to the probability menu, go to normal distribution choices, I can get an immediate calculation of cumulative probability and other normal distribution calculations for the X values that were entered by the summation key. I'm wondering how to switch things so that the normal distribution calculations can be done on the y values that were entered with the summation key.
(05-04-2017 05:42 PM)lrdheat Wrote: [ -> ]I enter an X value, then a y value, and hit the summation key, and do so for my list of X and y values. If I then execute X-bar (mean X), X-bar AND y-bar are placed in the X and y display lines. If I enter some number into the command line, go to the probability menu, go to normal distribution choices, I can get an immediate calculation of cumulative probability and other normal distribution calculations for the X values that were entered by the summation key. I'm wondering how to switch things so that the normal distribution calculations can be done on the y values that were entered with the summation key.

If you press X-bar the two means are placed in X and Y. If you want to continue with the y-value, simply press X<>Y.

But I think I still do not understand what your problem is. So once again: please provide a detailled example with values and all keys pressed.

Dieter
Entering average monthly daily high and low temperatures for Laredo. They do not approximate a normal distribution, but will serve to illustrate. 46 enter 68 summation, 50 enter 73 summation, 56 enter 81 summation, 64 enter 88 summation, 71 enter 95 summation, 75 enter 99 summation, 76 enter 100 summation, 76 enter 100 summation, 72 enter 94 summation, 65 enter 88 summation, 54 enter 77 summation, 46 enter 68 summation.

Press X-bar, get 85.92 in X display line, 62.75 in y display line.

If I type 66 in the command line, go to probability menu, and choose Norml, I get .05 which is correct for the X values that I have entered (high temperatures)...correctly showing that 66 is on the lower end of the cumulative distribution.

My question is, how do I switch the X and Y summations so that I can type in 66, go to probability menu, execute Norml, and get .61, showing that for low of the days, I'm in the meat of the distribution.
It is not difficult to call up X-bar, swap X and y, store result in j, call up standard dev s, swap X and y, store result in k, and then do the calculation (.61 comes up correctly). I was wondering if I could simply switch the X and y summations themselves, avoiding the manual entering of y-bar and y standard deviation...
Just now realized that, even with 1 variable statistics, I had to manually enter X-bar into j and X standard d into k. For some reason, I thought those values were automatically entered!
Write a small keystroke program to do what you want.
You already know most of the steps.

Pauli
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