How to add percentile lines in probability plot?

[#1]

example: suppose I want to mark the 90th percentile on Y axis and link it to its corresponding value on x-axis on a probability plot.

How can this  be done? Thanks

[#2]

The answer depends on many things. For example,

• Do you want to work interactively or use a script?
• Are you using a built-in plot (e.g., Normal Quantile Plot in Distribution) or a custom plot (e.g., Picture Box object)?
• How do you want to mark the 90th percentile? A line?
• How is the percentile determined? Is it the empirical distribution, such as used in Quantiles report from Distribution? Is it from a fitted distribution model?

[#3]

1. I work interactively 100%

2. Using a built in plot (e.g., Normal Quantile Plot in Distribution)

3. A line (L - shaped) going from 90th percentile on Y axis and connecting to corresponding value on X axis

4. The percentile is choosen

Please see attached JPG for reference.. thanks

[#4 · Accepted solution]

See Help > Books > Essential Graphing for more details.

You can use the Line and Annotation tools to add these graphic elements to your plot with the mouse.

Alternatively, you can right-click inside the plot frame and select Customize. You will have to add some scripting expressions. The Pen Color( "red" ), H Line( x min, x max, 90 ), V Line( quantile, y min, y max ), and Text( CounterClockwise, "quantile" ) would be all you need.

[#5]

What if you need to draw a line for each categorical value you have in the X AXIS? The customized scripting does not work that way. Additionally the bar or line drop down menu (red triangle) doesn't include an option for the summary statistic to be a quantile.