Probability graph paper

normal

A specially scaled graph paper which is so constructed that the graph of the normal distribution function is represented on it by a straight line. This is achieved by varying the scale of the vertical axis (see Fig.). This "rectification" property is the principle of verification whether or not a given sample is drawn from a normal distribution: If the empirical distribution function, plotted on probability graph paper, approximates a straight line, it may be reliably concluded that the population out of which the sample has been chosen has approximately a normal distribution. The advantage of this method consists in the fact that normality of a distribution may be deduced from a sample without knowledge of the parameters of the hypothetical distribution. The straight line represents the normal distribution function with average 100 and standard deviation 8.

Figure: p074910a

References

[1]	N. Arley, K.R. Buch, "Introduction to the theory of probability and statistics" , Wiley (1950)
[2]	W.J. Dixon, F.J. Massey, "Introduction to statistical analysis" , McGraw-Hill (1957)