Little D I, Poat P C, Giles I G
Eur J Biochem. 1982 Jun;124(3):499-505. doi: 10.1111/j.1432-1033.1982.tb06621.x.
The nature of the experimental error in the initial velocities of an enzyme-catalysed reaction is required if meaningful least-squares regression is to be applied. When a rate equation more complex that that of Michaelis and Menten is to be solved least-squares techniques are the method of choice and so determination of the error structure becomes mandatory. The use of residual analysis and Tukey's T statistics to determine the weights to use are described. This method has the advantage of requiring no additional experimentation over that required for the primary investigation. Using data obtained for Carcinus maenas phosphofructokinase the variance was found to increase with velocity and was approximated by either an empirical power function, var (vi) alpha vi1.8 or by the function, var (vi) alpha 0.007 + vi2. The latter function is preferred and suggests that the data contains both a constant absolute error and a constant percentage error component.
如果要应用有意义的最小二乘回归，就需要了解酶催化反应初速度实验误差的性质。当要求解比米氏方程更复杂的速率方程时，最小二乘技术是首选方法，因此确定误差结构就变得必不可少。文中描述了如何使用残差分析和图基T统计量来确定权重。这种方法的优点是，除了初步研究所需的实验外，不需要额外的实验。利用从食蟹猴磷酸果糖激酶获得的数据，发现方差随速度增加，并且可以用经验幂函数var(vi)∝vi1.8或函数var(vi)∝0.007 + vi2来近似。后一种函数更可取，表明数据包含恒定的绝对误差和恒定的百分比误差成分。
