对于两条线性回归直线（使用最小二乘法），估计的斜率为b1和b2，我们可以使用协方差分析来比较其差异的显著性。

现在：
During checking the relationship between leaf weight (LW) and and leaf area (LA), we usually use the following power function:

LA = a * LW ^ b, which could be rewritten as:

log(LA) = c + b * log(LW), where c = log(a).




Assume that there are six species, and we attempt to compare the estimates of six estimates of slopes. Some investigators suggest using the reduced major axis (RMA) to estimate the parameters c and b. In this case, which method is suitable for testing whether there are significant diference in slopes between these six species?

每个物种我们有200片叶子的重量和面积。我们需要使用RMA吗？如果使用RMA，那么如何检验其斜率估计值差异是否具有显著性呢（使用什么方法）？

谢谢！