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Two Means - Unknown, Equal Variance
10. Hypothesis Testing for Two Samples / Two Means - Unknown, Equal Variance / Problem 3
Problem 3

Two independent samples are drawn to compare variability.
Sample A: {1010, 1212, 99, 1111, 1313, 1010, 1414, 88, 1212}
Sample B: {77, 99, 66, 88, 77, 99, 55, 88}
Use the "count five" test: compute medians, absolute deviations from medians, maxima of absolute deviations M1M_1, M2M_2, counts c1c_1, c2c_2 where c1=#{d1i:d1i>M2}c_1=\#\{d_{1i}:d_{1i}>M_2\} and c2=#{d2j:d2j>M1}c_2=\#\{d_{2j}:d_{2j}>M_1\}, and reject the null hypothesis (equal variances) if max(c1,c2)5\(\max\)(c_1,c_2)\(\ge\) 5. Which conclusion is correct?