Plot on Probability paper (simple X-axis and probability Y-axis)

Grain size
-1
-0.5
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
percentage values

28.56
41.25
46.94
52.14
59.82
74.26
90.12
98.24
99.78
99.87
99.93
99.99
100.00

These are the Grain size(-1 to 5) and percentage values(up to 100).Please help me by suggesting how to plot these kind of graph having simple X-axis and probability Y-axis?

Answer 1

[Star Strider]

If you have the Statistics Toolbox, use the probplot function.

[KOUSHIK SAHA]

If x=[-1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5] and y=[28.56 41.25 46.94 52.14 59.82 74.26 90.12 98.24 99.78 99.87 99.93 99.99 100.00] Then i use the function plot(x,y) then I get the curve(on simple graph paper) and If I use the probplot(x,y) the I get two different lines for individual x and y values (In probability paper). But how to get a single line from problot like from plot(x,y) ?

[Star Strider]

The probplot function is for raw data. If you already have the probabilities, you don’t need probplot. Just use plot. The advantage of using probplot with raw data is the axis scaling.

[KOUSHIK SAHA]

Thank you for your answer.I just want to plot my x,y value in Probability paper, but I can't plot it by using 'plot' function.

[Star Strider]

My pleasure.

The only way I know of to do that is to take the inverse normal distribution of your probabilities and plot them:

x=[-1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5];
y=[28.56 41.25 46.94 52.14 59.82 74.26 90.12 98.24 99.78 99.87 99.93 99.99 100.00];

yinv = norminv(y/101, 0, 1);                            % Take Inverse Normal Probability of ‘y’

figure(1)
probplot(yinv)
grid

I don’t know if this give you the result you want, but it’s the only solution I can provide with the data you posted.

[Peter Bohn]

It doesn't seem like this question has been answered completely.

Is there a way to change the scale of the y axis of the normal plot() function to mimick a normal probability distribution?

I have the same issue the person asking the question has. I have x and y data, but it is standard practice to use probability paper for ploting the distribution of grain sizes in sand samples.

[Abigail Cafferty]

I also am looking for a way to make the x axis have probability scaling, instead of the y. From what it seems, you can only use the normplot() function to scale the y axis.