A Modified Sign Test for Symmetry

We propose a new test for symmetry about a known center. The test utilizes information on both absolute ranks and signs of the sample. It is shown by Monte Carlo study to be more powerful than the modified runs test proposed by Modarres and Gastwirth [Modarres, R., Gastwirth, J. L. (1996). A modified runs test for symmetry. Stat. Prob. Lett. 31:107–112] and hence also more powerful than the sign test and Wilcoxon signed rank test against alternatives in the lambda family.