Different regression equations relate age to the incidence of Lauren types 1 and 2 stomach cancer in the SEER database: these equations are unaffected by sex or race

Table 9 Quantitative assessments of model adequacy.

Shapiro-Wilks normality test performed on standardized residuals.
	W	P
Without outlier	0.984	0.06
With outlier	0.960	0.0001
T test to see if mean of standardized residuals was not zero.
	Mean	T	df	P
Without outlier	-0.003	-0.03	158	0.97
With outlier	-0.003	-0.03	159	0.97
Bartlett's test to see if the standardized residuals, divided into four groups by their corresponding fitted values, lacked constant variances.
	K²	Df	P
Without outlier	4.43	3	0.22
With outlier	15.02	3	0.002

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