Dear all,
As you know, before the ANOVA or t-test, we should test the normality of our data. Sometimes the transformation of our data is necessary, now I have a question, my data contains both positive and negative( such as 1, 2, -8, -5........). So, which kind of transformation should I take?
2011-01-12
Yong Zhang, Ph.D.
Lab of aquatic insects & stream ecology
Dept.of Entonology, Nanjing Agricultural University
Nanjing, 210095,China
Phone number: (+86) -25-84395241
E-mail:2010202035 at njau.edu.cn