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How to fit Rayleight / folded norma distributions ?

SophieCuvillier
Level IV

Hello,

 

Is it possible to fit Rayleight and folded normal distributions ? Just like we have the fit distribution platform, with goodness of fit metrics etc...

 

Best regards,

1 ACCEPTED SOLUTION

Accepted Solutions
Byron_JMP
Staff


Re: How to fit Rayleight / folded norma distributions ?

maybe take a look at the Gamma family of distributions, specifically the Weibull distribution. 

also, in the life distribution platform you can fit a mixture of distributions, 

Screenshot 2025-03-19 at 2.17.46 PM.png

 This data set using 10000 rows with this formula:   

Abs( Random Normal( 1, 1 ) )

 

Analyze>Reliability>Life Distribution, I picked the formula col for the time to event and from the red triangle picked fit mixture.  This shows up at the bottom of the report, I click Weibull twice, and then clicked Go

 

Screenshot 2025-03-19 at 2.18.58 PM.png

 

Life Distribution(
	Y( :Column 3 ),
	Confidence Interval Method( Wald ),
	Interval Type( Pointwise ),
	Show Event Plot Frequency Label( 0 ),
	Fit Mixture( Mix( Weibull( 2 ), Overlapping Clusters, Show Profilers( 0 ) ) ),
	SendToReport(
		Dispatch( {"Mixture", "Overlay"}, "5", ScaleBox,
			{Format( "Fixed Dec", 12, 1 ), Min( -0.0507969202844342 ),
			Max( 1.05079692028443 ), Inc( 0.2 ), Minor Ticks( 0 )}
		),
		Dispatch( {"Mixture", "Overlay"}, "4", ScaleBox,
			{Format( "Fixed Dec", 12, 0 ), Min( -0.401614772053014 ),
			Max( 5.23133596019622 ), Inc( 1 ), Minor Ticks( 0 )}
		)
	)
);

JMP Systems Engineer, Health and Life Sciences (Pharma)

View solution in original post

2 REPLIES 2
Byron_JMP
Staff


Re: How to fit Rayleight / folded norma distributions ?

maybe take a look at the Gamma family of distributions, specifically the Weibull distribution. 

also, in the life distribution platform you can fit a mixture of distributions, 

Screenshot 2025-03-19 at 2.17.46 PM.png

 This data set using 10000 rows with this formula:   

Abs( Random Normal( 1, 1 ) )

 

Analyze>Reliability>Life Distribution, I picked the formula col for the time to event and from the red triangle picked fit mixture.  This shows up at the bottom of the report, I click Weibull twice, and then clicked Go

 

Screenshot 2025-03-19 at 2.18.58 PM.png

 

Life Distribution(
	Y( :Column 3 ),
	Confidence Interval Method( Wald ),
	Interval Type( Pointwise ),
	Show Event Plot Frequency Label( 0 ),
	Fit Mixture( Mix( Weibull( 2 ), Overlapping Clusters, Show Profilers( 0 ) ) ),
	SendToReport(
		Dispatch( {"Mixture", "Overlay"}, "5", ScaleBox,
			{Format( "Fixed Dec", 12, 1 ), Min( -0.0507969202844342 ),
			Max( 1.05079692028443 ), Inc( 0.2 ), Minor Ticks( 0 )}
		),
		Dispatch( {"Mixture", "Overlay"}, "4", ScaleBox,
			{Format( "Fixed Dec", 12, 0 ), Min( -0.401614772053014 ),
			Max( 5.23133596019622 ), Inc( 1 ), Minor Ticks( 0 )}
		)
	)
);

JMP Systems Engineer, Health and Life Sciences (Pharma)


Re: How to fit Rayleight / folded norma distributions ?

Hello, Thank you very much for your answer, I will try to do that !