A recent study interviewed youths with a battery of questions that provides a summary measure of perceived parental support. This measure had sample means of 46 (s = 9) for the single-mother households and 42 (s = 10) for the households with both biological parents. One conclusion in the study stated, “The mean parental support was 4units higher for the single-mother households. If the true means were equal, a difference of at least this size could be expected only 2% of the time. For samples of this size, 95% of the time one would expect this difference to be within 3.4 of the true value.” Explain how this conclusion refers to the results of
(a) A Confidence interval and
(b) A significance test.