In a sample of 17 participants,a researcher estimates the 90% CI for a sample with a mean of M_D = 7 and an estimated standard error for the difference scores (S_MD)of 2.2.What is the confidence interval at this level of confidence? A) 90% CI 2.4, 11.6 B) 90% CI 3.2, 10.8 C) 90% CI 4.8, 9.2 D) There is not enough information to answer this question.

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Quizplus · Accepted Answer

The 90% confidence interval is calculated using the formula: M_D ± (t * S_MD). With 16 degrees of freedom (n-1=17-1), the t-value for 90% CI is approximately 1.746. Thus, the interval is 7 ± (1.746 * 2.2), which results in 3.2 to 10.8.

In a Sample of 17 Participants,a Researcher Estimates the 90