One-sample t-test - Radford

a Z-test and we were doing a directional test, we’d use a critical value of +1.645. That critical value is a value for Z, but we’re not doing a Z-test. We can’t compare an observed value for t to a critical value for Z. We need to compare apples to apples. We’ve got to figure out what the critical value for t ought to be. ................
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