One-sample t test
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Variable | Obs Mean Std. Err. Std. Dev. [95% Conf. Interval]
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CAR | 41 -.0005051 .0001685 .0010791 -.0008458 -.0001645
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mean = mean(CAR) t = -2.9974
Ho: mean = 0 degrees of freedom = 40
Ha: mean < 0 Ha: mean != 0 Ha: mean > 0
Pr(T < t) = 0.0023 Pr(|T| > |t|) = 0.0047 Pr(T > t) = 0.9977