Simple regression was employed to establish the effects ofchildhood exposure to lead. The effective sample size was about 122subjects. The independent variable was the level of dentin lead(parts per million). Below are regressions using various dependentvariables.

(a) Calculate the t statistic for each slope. Fromthe p-values, which slopes differ from zero at α = .01?(Round your answers to 2 decimal places. Negative valuesshould be indicated by a minus sign.)

Dependent Variable	R2	Estimated Slope	Std Error	tcalculated	p-value		Differ from 0?
Highest grade achieved		0.050			-0.029			0.010						.004			(Click to select)  No  Yes
Reading grade equivalent		0.126			-0.093			0.022						.000			(Click to select)  Yes  No
Class standing		0.078			-0.005			0.002						.014			(Click to select)  Yes  No
Absence from school		0.073			4.700			1.620						.004			(Click to select)  No  Yes
Grammatical reasoning		0.090			0.132			0.070						.062			(Click to select)  No  Yes
Vocabulary		0.119			-0.196			0.002						.000			(Click to select)  Yes  No
Hand-eye coordination		0.035			0.060			0.027						.028			(Click to select)  Yes  No
Reaction time		0.016			9.300			3.560						.010			(Click to select)  No  Yes
Minor antisocial behavior		0.037			-0.819			0.579						.160			(Click to select)  No  Yes

(b) It would be inappropriate to assume cause andeffect without a better understanding of how the study wasconducted.

• Yes

• No