. * nwsaom tutorial 2: reading convergence, and what to do when it fails . * Requires the core nwcommands and the package nwsaom. . . nwwebuse glasgow, nwclear . . * A rich model estimated with a deliberately short third phase (k3(100)): . * the estimates are noisy and the run does not converge . nwsaom, waves(glasgow1 glasgow2 glasgow3) outdegree reciprocity gwesp(.69) indegpopularity outactivity egox(alcohol1) > altx(alcohol1) simx(alcohol1) samex(smoke1) transtrip cycle3 seed(1) k3(100) detail ------------------------------------------------------------------------------------------------------------------------- SAOM (Method of Moments, conditional), waves: glasgow1 glasgow2 glasgow3 Actors: 50 Periods: 2 ------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------- glasgow1_to_g~3 | Coefficient Std. err. z P>|z| [95% conf. interval] ----------------+---------------------------------------------------------------- outdegree | -1.209788 .6076227 -1.99 0.046 -2.400707 -.0188697 reciprocity | 2.263883 .529079 4.28 0.000 1.226907 3.300859 samex_smoke1 | .1610482 .2266739 0.71 0.477 -.2832245 .6053209 altx_alcohol1 | .006889 .1107258 0.06 0.950 -.2101297 .2239076 egox_alcohol1 | .1359848 .1114579 1.22 0.222 -.0824685 .3544382 indegpopularity | -.6466204 .4983963 -1.30 0.194 -1.623459 .3302184 outactivity | -.1646595 .0717318 -2.30 0.022 -.3052512 -.0240677 transtrip | -1.179726 1.512629 -0.78 0.435 -4.144425 1.784972 cycle3 | 1.029549 1.018194 1.01 0.312 -.9660754 3.025173 gwesp_.69 | 3.840171 3.118244 1.23 0.218 -2.271475 9.951818 simx_alcohol1 | .5145673 .3656165 1.41 0.159 -.202028 1.231163 ------------------------------------------------------------------------------------------------------------------------- Rate parameters (estimated, one per inter-wave period): | period1 period2 -------------+--------------------- rate | 6.7516 4.9774 se | 1.1937 0.9694 (conditional: rate = mean time to reach the observed distance, se = its SD) RSiena effect names: samex_smoke1 same smoke1 altx_alcohol1 alcohol1 alter egox_alcohol1 alcohol1 ego gwesp_.69 GWESP I -> K -> J (69) simx_alcohol1 alcohol1 similarity Covariates centred by their means, as RSiena's coCovar(centered = TRUE): alcohol1 2.880 Convergence t-ratios (criterion: every |t| below 0.1; the overall maximum ratio below 0.25 is a separate criterion): outdegree 0.199 reciprocity 0.165 samex_smoke1 0.049 altx_alcohol1 0.300 egox_alcohol1 0.241 indegpopularity 0.201 outactivity 0.238 transtrip 0.213 cycle3 0.192 gwesp_.69 0.215 simx_alcohol1 0.201 Overall maximum convergence ratio: 0.427 . . * The convergence t-ratios are stored . matrix list e(tconv) e(tconv)[1,11] outdegree reciprocity samex_smoke1 altx_alcoh~1 egox_alcoh~1 indegpopul~y outactivity transtrip tconv .19864068 .1645989 .04859904 .29953977 .24109886 .20086809 .23756474 .21284053 cycle3 gwesp_.69 simx_alcoh~1 tconv .19159416 .21507889 .20131954 . . * Restart from the estimates: pass them as starting values . matrix b = e(b) . local th . forvalues j = 1/`=colsof(b)' { 2. local th `th' `=b[1,`j']' 3. } . display "`th'" -1.209788342910449 2.263883290175197 .1610482008999299 .0068889647862135 .1359848318693541 -.6466204039545523 -.16465947 > 7141032 -1.179726289641548 1.029548730367219 3.840171283459446 .5145672925764175 . nwsaom, waves(glasgow1 glasgow2 glasgow3) outdegree reciprocity gwesp(.69) indegpopularity outactivity egox(alcohol1) > altx(alcohol1) simx(alcohol1) samex(smoke1) transtrip cycle3 seed(2) theta0(`th') detail ------------------------------------------------------------------------------------------------------------------------- SAOM (Method of Moments, conditional), waves: glasgow1 glasgow2 glasgow3 Actors: 50 Periods: 2 ------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------- glasgow1_to_g~3 | Coefficient Std. err. z P>|z| [95% conf. interval] ----------------+---------------------------------------------------------------- outdegree | -1.20907 .5609371 -2.16 0.031 -2.308487 -.1096537 reciprocity | 2.280546 .2646771 8.62 0.000 1.761789 2.799304 samex_smoke1 | .1680516 .1960388 0.86 0.391 -.2161774 .5522807 altx_alcohol1 | -.0002235 .0776939 -0.00 0.998 -.1525007 .1520538 egox_alcohol1 | .1379253 .1047766 1.32 0.188 -.067433 .3432837 indegpopularity | -.6432866 .3120702 -2.06 0.039 -1.254933 -.0316402 outactivity | -.1674719 .0622312 -2.69 0.007 -.2894428 -.045501 transtrip | -1.192036 .806658 -1.48 0.139 -2.773056 .3889849 cycle3 | 1.015119 .5305186 1.91 0.056 -.0246787 2.054916 gwesp_.69 | 3.876746 1.589124 2.44 0.015 .7621203 6.991372 simx_alcohol1 | .4904613 .3493353 1.40 0.160 -.1942234 1.175146 ------------------------------------------------------------------------------------------------------------------------- Rate parameters (estimated, one per inter-wave period): | period1 period2 -------------+--------------------- rate | 6.5281 5.0094 se | 1.1808 0.8427 (conditional: rate = mean time to reach the observed distance, se = its SD) RSiena effect names: samex_smoke1 same smoke1 altx_alcohol1 alcohol1 alter egox_alcohol1 alcohol1 ego gwesp_.69 GWESP I -> K -> J (69) simx_alcohol1 alcohol1 similarity Covariates centred by their means, as RSiena's coCovar(centered = TRUE): alcohol1 2.880 Convergence t-ratios (criterion: every |t| below 0.1; the overall maximum ratio below 0.25 is a separate criterion): outdegree 0.063 reciprocity 0.056 samex_smoke1 0.049 altx_alcohol1 0.025 egox_alcohol1 0.022 indegpopularity 0.069 outactivity 0.062 transtrip 0.058 cycle3 0.052 gwesp_.69 0.060 simx_alcohol1 -0.005 Overall maximum convergence ratio: 0.091 . . * Wald tests with Stata's own commands . test egox_alcohol1 = altx_alcohol1 ( 1) - altx_alcohol1 + egox_alcohol1 = 0 chi2( 1) = 0.98 Prob > chi2 = 0.3234 . lincom egox_alcohol1 - altx_alcohol1 ( 1) - altx_alcohol1 + egox_alcohol1 = 0 ------------------------------------------------------------------------------------------------------------------------- glasgow1_t~3 | Coefficient Std. err. z P>|z| [95% conf. interval] -------------+---------------------------------------------------------------- (1) | .1381488 .1399055 0.99 0.323 -.136061 .4123586 ------------------------------------------------------------------------------------------------------------------------- .