Hello,

I am in the process of building a regression model with a DV (q_tot), an IV (rdalliances), a moderators(munificence), and some controls which looks like this:
Code:
Code:
 xtreg q_tot c.rdalliances##c.rdalliances##c.munificence rdi_w adi_w ln_emp1_w lev i.fyear, re vce(robust)
Now I want to test for a shift of turning point for different values of the moderator "munificence" according to Haans et al. (2016) "THINKING ABOUT U: THEORIZING AND TESTING U- AND INVERTED U-SHAPED RELATIONSHIPS IN STRATEGY RESEARCH".

For that, I want to use the following mile stone values:
Minimum = -4798.703 ; -1
standard deviation = -994.669201;
Mean = 4.517799;
+1 standard deviation = 1003.704799;
Maximum = 323551.7)

The code:
Code:
    xtreg q_tot c.rdalliances##c.rdalliances##c.munificence rdi_w adi_w ln_emp1_w lev i.fyear, re vce(robust)


    foreach munificence in -4798.703 -994.669201 4.517799 1003.704799 323551.7 {
        nlcom (_b[rdalliances]*_b[c.rdalliances#c.rdalliances#c.munificence] - _b[c.rdalliances#c.rdalliances]*_b[c.rdalliances#c.munificence]) / 2*(_b[c.rdalliances#c.rdalliances]+_b[c.rdalliances#c.rdalliances#c.munificence]*(`munificence'))^2
    }
But I keep getting an error message that says "Maximum numbers of iterations exceeded".

Does someone know how to handle this problem or what my specific error here is?

Thanks in advance!
Hanna