On 3 March 2017 at 19:51, Mahdi, Sam <sam.mahdi....@my.csun.edu> wrote: > Hello everyone, > > This isn't as much a problem with relax as it is a general question > regarding S^2 values itself. When comparing different values of S^2 between > proteins, what difference is considered significant. Due to the lower > values I know say an average S^2 value of .1 is a big difference in the > flexibility of one protein to another, but what about say an average > difference of .01, is that still considered a significant change in > considering the relative dynamics of one protein to another? (I.e. if say, > protein A has an average S^2 value of 9, and protein B has an average S^2 > value of 8.9, could you make the statement Protein A has significant > dynamic differences, more rigid, when compared to Protein B. Or could you > make the statement due to only a difference of .01, there isn't much of a > overall dynamic difference between the 2 proteins)?
Hi Sam, Sorry for not getting back to you earlier, I have been extremely busy lately! This is really a statistical problem. And it depends on the quality of your parameter error estimates. If you have two values and two associated errors, then you can look at hypothesis testing / ANOVA statistics to tell you if the two values are statistically different (i.e. 1st year Uni stats). Note that your error estimates should include the variability of the diffusion tensor, as that will account for probably around 80% of the influence on the relaxation data, and without this variability a S2 parameter comparison is meaningless. There is no rule for S2 differences so you need to rely on basic statistical tests. Regards, Edward _______________________________________________ relax (http://www.nmr-relax.com) This is the relax-users mailing list relax-users@gna.org To unsubscribe from this list, get a password reminder, or change your subscription options, visit the list information page at https://mail.gna.org/listinfo/relax-users