Plotting Points on Normal Probability Paper: Tips & Tricks

[axnman]

Jus some confusion over plotting points on normal probability paper..

1. Order the data
2. Do we do (i-0.5)/n where i=no. of observation and n= no. of samples?
believe can't use Z(i)= (X(i)- Mean)/ stand. dev. as i need to find both mean and std. dev from the graph...
What is the graph plotted for...i mean i have X(i) Vs Z(i) but seem a bit in circles.

can anybody please let me know?thanks

 

[HallsofIvy]

Jus some confusion over plotting points on normal probability paper..

1. Order the data

Okay, that should be easy.

2. Do we do (i-0.5)/n where i=no. of observation and n= no. of samples?

Do that for WHAT? I have no idea what you are taking about here.

believe can't use Z(i)= (X(i)- Mean)/ stand. dev. as i need to find both mean and std. dev from the graph...[\quote]
Use it for WHAT?

What is the graph plotted for...i mean i have X(i) Vs Z(i) but seem a bit in circles.

can anybody please let me know?thanks

What graph are you talking about? You don't actually state what your problem is!