I am currently on establishing relationship between fiscal variables and economic growth. I have encountered problems using xtpmg for the two following examples. If anyone might be able to explain source of errors or solutions, that would be very much appreciated.
The data contains n=21 with unbalanced information of t=41.
In the first case, I cannot get any results up to 53th iteration. In the second case, "numerical derivatives are approximate flat or discontinuous region encountered" keeps on repeating. Also, the variable soc_tot does not get any value apart from coefficient.
1.) xtpmg d.y d.tot_gdp d.distax_gdp d.tgs_gdp d.LG if Year>=1972, lr(l.y distax_gdp tot_gdp tgs_gdp LG)
This command results in following outputs.
Iteration 0: log likelihood = 1925.5649 (not concave)
Iteration 1: log likelihood = 1926.3796 (not concave)
Iteration 2: log likelihood = 1965.3657 (not concave)
Iteration 3: log likelihood = 1968.885 (not concave)
Iteration 4: log likelihood = 1977.1037
Iteration 5: log likelihood = 1981.2225 (not concave)
Iteration 6: log likelihood = 1982.0079 (not concave)
Iteration 7: log likelihood = 1982.0838 (not concave)
Iteration 8: log likelihood = 1982.0981 (not concave)
Iteration 9: log likelihood = 1982.1018 (not concave)
Iteration 10: log likelihood = 1982.1039 (not concave)
Iteration 11: log likelihood = 1982.1041 (not concave)
..........
Iteration 49: log likelihood = 1982.1041 (not concave)
Iteration 50: log likelihood = 1982.1041 (not concave)
Iteration 51: log likelihood = 1982.1041 (not concave)
Iteration 52: log likelihood = 1982.1041 (not concave)
Iteration 53: log likelihood = 1982.1041 (not concave)
I broke the computation at the 53th iteration without getting any output.
2.) xtpmg d.y d.tot_gdp d.distax_gdp d.tgs_gdp d.K d.LG soc_tot if Year>=1972, lr(l.y distax_gdp tgs_gdp tot_gdp soc_tot K LG) ec(ec) replace pmg
For this command, I do get the results with the following issues.
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 0: log likelihood = 2126.6005 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 1: log likelihood = 2168.4241 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 2: log likelihood = 2170.4069 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 3: log likelihood = 2171.9291
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 4: log likelihood = 2172.0204 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 5: log likelihood = 2172.0301 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 6: log likelihood = 2172.0317 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 7: log likelihood = 2172.032 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 8: log likelihood = 2172.0322 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 9: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 10: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 11: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 12: log likelihood = 2177.0971
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 13: log likelihood = 2178.56
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 14: log likelihood = 2178.7843
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 15: log likelihood = 2178.7935
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 16: log likelihood = 2178.7939
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 17: log likelihood = 2178.794
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 18: log likelihood = 2178.7942
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 19: log likelihood = 2178.7945
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 20: log likelihood = 2178.7945
Pooled Mean Group Regression
(Estimate results saved as pmg)
Panel Variable (i): OBS Number of obs = 745
Time Variable (t): Year Number of groups = 21
Obs per group: min = 14
avg = 35.5
max = 41
Log Likelihood = 2178.794
------------------------------------------------------------------------------
D.y | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
ec |
distax_gdp | .0024274 .0172667 0.14 0.888 -.0314147 .0362696
tgs_gdp | .099528 .0370827 2.68 0.007 .0268472 .1722088
tot_gdp | -.0786166 .0146998 -5.35 0.000 -.1074277 -.0498054
soc_tot | 7.034265 . . . . .
K | .0716078 .0171817 4.17 0.000 .0379322 .1052834
LG | -.0765695 .0358488 -2.14 0.033 -.1468319 -.0063072
-------------+----------------------------------------------------------------
SR |
ec | -.0136021 .004741 -2.87 0.004 -.0228943 -.0043099
|
tot_gdp |
D1. | -.0035354 .0008219 -4.30 0.000 -.0051463 -.0019245
|
distax_gdp |
D1. | .0011868 .0010087 1.18 0.239 -.0007903 .0031638
|
tgs_gdp |
D1. | -.0038713 .0024882 -1.56 0.120 -.008748 .0010054
|
K |
D1. | .0054049 .000592 9.13 0.000 .0042446 .0065652
|
LG |
D1. | .0016224 .0009967 1.63 0.104 -.0003311 .003576
|
soc_tot | -.0969039 .0334432 -2.90 0.004 -.1624514 -.0313563
_cons | .2060211 .0573896 3.59 0.000 .0935396 .3185026
------------------------------------------------------------------------------
I am very curious why the message "numerical derivatives are approximate flat or discontinuous region encountered" keeps on repeating. Also, the variable soc_tot does not get any value apart from coefficient.
Thank you very much in advance. Look forward to your reply.
Best regards,
Kritchasorn
The data contains n=21 with unbalanced information of t=41.
In the first case, I cannot get any results up to 53th iteration. In the second case, "numerical derivatives are approximate flat or discontinuous region encountered" keeps on repeating. Also, the variable soc_tot does not get any value apart from coefficient.
1.) xtpmg d.y d.tot_gdp d.distax_gdp d.tgs_gdp d.LG if Year>=1972, lr(l.y distax_gdp tot_gdp tgs_gdp LG)
This command results in following outputs.
Iteration 0: log likelihood = 1925.5649 (not concave)
Iteration 1: log likelihood = 1926.3796 (not concave)
Iteration 2: log likelihood = 1965.3657 (not concave)
Iteration 3: log likelihood = 1968.885 (not concave)
Iteration 4: log likelihood = 1977.1037
Iteration 5: log likelihood = 1981.2225 (not concave)
Iteration 6: log likelihood = 1982.0079 (not concave)
Iteration 7: log likelihood = 1982.0838 (not concave)
Iteration 8: log likelihood = 1982.0981 (not concave)
Iteration 9: log likelihood = 1982.1018 (not concave)
Iteration 10: log likelihood = 1982.1039 (not concave)
Iteration 11: log likelihood = 1982.1041 (not concave)
..........
Iteration 49: log likelihood = 1982.1041 (not concave)
Iteration 50: log likelihood = 1982.1041 (not concave)
Iteration 51: log likelihood = 1982.1041 (not concave)
Iteration 52: log likelihood = 1982.1041 (not concave)
Iteration 53: log likelihood = 1982.1041 (not concave)
I broke the computation at the 53th iteration without getting any output.
2.) xtpmg d.y d.tot_gdp d.distax_gdp d.tgs_gdp d.K d.LG soc_tot if Year>=1972, lr(l.y distax_gdp tgs_gdp tot_gdp soc_tot K LG) ec(ec) replace pmg
For this command, I do get the results with the following issues.
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 0: log likelihood = 2126.6005 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 1: log likelihood = 2168.4241 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 2: log likelihood = 2170.4069 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 3: log likelihood = 2171.9291
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 4: log likelihood = 2172.0204 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 5: log likelihood = 2172.0301 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 6: log likelihood = 2172.0317 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 7: log likelihood = 2172.032 (backed up)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 8: log likelihood = 2172.0322 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 9: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 10: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 11: log likelihood = 2172.0323 (not concave)
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 12: log likelihood = 2177.0971
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 13: log likelihood = 2178.56
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 14: log likelihood = 2178.7843
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 15: log likelihood = 2178.7935
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 16: log likelihood = 2178.7939
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 17: log likelihood = 2178.794
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 18: log likelihood = 2178.7942
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 19: log likelihood = 2178.7945
numerical derivatives are approximate
flat or discontinuous region encountered
Iteration 20: log likelihood = 2178.7945
Pooled Mean Group Regression
(Estimate results saved as pmg)
Panel Variable (i): OBS Number of obs = 745
Time Variable (t): Year Number of groups = 21
Obs per group: min = 14
avg = 35.5
max = 41
Log Likelihood = 2178.794
------------------------------------------------------------------------------
D.y | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
ec |
distax_gdp | .0024274 .0172667 0.14 0.888 -.0314147 .0362696
tgs_gdp | .099528 .0370827 2.68 0.007 .0268472 .1722088
tot_gdp | -.0786166 .0146998 -5.35 0.000 -.1074277 -.0498054
soc_tot | 7.034265 . . . . .
K | .0716078 .0171817 4.17 0.000 .0379322 .1052834
LG | -.0765695 .0358488 -2.14 0.033 -.1468319 -.0063072
-------------+----------------------------------------------------------------
SR |
ec | -.0136021 .004741 -2.87 0.004 -.0228943 -.0043099
|
tot_gdp |
D1. | -.0035354 .0008219 -4.30 0.000 -.0051463 -.0019245
|
distax_gdp |
D1. | .0011868 .0010087 1.18 0.239 -.0007903 .0031638
|
tgs_gdp |
D1. | -.0038713 .0024882 -1.56 0.120 -.008748 .0010054
|
K |
D1. | .0054049 .000592 9.13 0.000 .0042446 .0065652
|
LG |
D1. | .0016224 .0009967 1.63 0.104 -.0003311 .003576
|
soc_tot | -.0969039 .0334432 -2.90 0.004 -.1624514 -.0313563
_cons | .2060211 .0573896 3.59 0.000 .0935396 .3185026
------------------------------------------------------------------------------
I am very curious why the message "numerical derivatives are approximate flat or discontinuous region encountered" keeps on repeating. Also, the variable soc_tot does not get any value apart from coefficient.
Thank you very much in advance. Look forward to your reply.
Best regards,
Kritchasorn