tag:blogger.com,1999:blog-4409551172339639840.post1436315104877424153..comments2018-09-22T01:18:01.839-07:00Comments on Douglas L. Campbell: On the Uses (and Abuses) of Economath: The Malthusian ModelsDoug Campbell http://www.blogger.com/profile/11028049845008665877noreply@blogger.comBlogger28125tag:blogger.com,1999:blog-4409551172339639840.post-14402193727281257532018-08-21T01:53:27.785-07:002018-08-21T01:53:27.785-07:00All of your blogs are up to date, i appreciate you...All of your blogs are up to date, i appreciate your work. Keep going and update us with your latest and fresh blogs.<br /><a href="https://www.wealthbuildup.com" rel="nofollow">Share market calls</a><br /><a href="https://www.wealthbuildup.com/option-call-put-service/" rel="nofollow">option call put tips</a><br /><a href="https://www.wealthbuildup.com/" rel="nofollow">SEBI Registered Investment advisor`</a><br /><br />wealth builduphttps://www.blogger.com/profile/14037672298317713029noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-21126431019760404342018-08-04T03:40:47.412-07:002018-08-04T03:40:47.412-07:004
IL CIUCCIA E PRENDI MEGA CAZZI A GO GO LUIGI BE...4<br /><br />IL CIUCCIA E PRENDI MEGA CAZZI A GO GO LUIGI BERLUSCONI (BACIO RICCHIONESCHISSIMO QUI http://www.si24.it/wp-content/uploads/2017/07/luigi-berlusconi--600x300.jpg ) NATO IN FIGHETTINA ARLESHEIM (CH) IL 27.9.1988.... L'OMOSESSUALE ^OCCULTO^ LUIGI BERLUSCONI http://www.leggo.it/gossip/news/luigi_berlusconi_bacio_sulla_bocca_ad_un_amico_la_barba-2548577.html<br />DI BASTARDAMENTE CRIMINALE ELIGOTECH AMSTERAM, BASTARDAMENTE CRIMINALE SOLDO LTD LONDON E BASTARDAMENTE CRIMINALE BANCA MEDIOLANUM (CHE RICICLANO MONTAGNE DI € MAFIOSI, ESATTAMENTE COME FACEVA LA CRIMINALISSIMA BANCA RASINI DI SUO NONNO, TOPO DI FOGNA LUIGI BERLUSCONI ....O COME FACEVA E FA ORA PIU' CHE MAI, LA FININVEST DEL PEDOFILO DILANIANTE FALCONE E BORSELLINO: SILVIO BERLUSCONI<br />http://www.vnews24.it/2014/05/29/borsellino-sentenza-choc-stragi-commissionate-berlusconi/<br />E DELLA CRIMINALISSIMA, HITLERIANA, ^OCCULTA" LESBICA MARINA BERLUSCONI )<br />INSIEME AL BERLUS-CO-RROTTO VERME MARCO CARRAI DI CGNAL, CREA NAZITECNOLOGICHE NUOVE OVRA E GHESTAPO! COL NOTO ANTI SEMITA, GIA' 3 VOLTE FINITO IN CARCERE, PAOLO BARRAI, NATO A MILANO IL 28.6.1965 ( FINITO IN CARCERE PURE IN BRASILE, ED ANCHE PER PEDOFILIA OMOSESSUALE: INCULAVA LI I BAMBINI, NE SCRIVEREMO PRESTO<br />http://www.rotadosertao.com/images/fotos/fotos_noticias/testao.jpg<br />http://4.bp.blogspot.com/-aqbT4KlYsmw/TcLbvUUpkeI/AAAAAAAAAe4/TiDPLR0LH_U/s1600/barrai+ind-pag01.jpg<br />https://groups.google.com/forum/#!topic/comp.soft-sys.matlab/j3oyd-SmJ88 )! UNITI AL MEGA RICICLA SOLDI ALTRETTANTO CRIMINALI: CAROGNA SCHIFOSA, MEGA FIGLIO E MARITO DI PUTTANONE, DAVIDE SERRA DI ALGEBRIS INVESTMENTS ( NON PER NIENTE, SOCIO DEI VERMI MEGA RICICLA SOLDI MAFIOSI: ENNIO DORIS, MASSIMO DORIS, GIOVANNI PIROVANO ED OSCAR DI MONTIGNY DI BANCA MEDIOLANUM, COSANOSTRANUM, CAMORRANUM, NDRANGOLANUM, HITLERANUM)! E COL TUTTO CONNESSO ALL'ECONOMISTA NOTORIAMENTE PEDERASTA E NAZISTA PAOLO CARDENÀ, NATO A MACERATA IL 2.19.1971 E RESIDENTE A PENNA SAN GIOVANNI (MACERATA), VIA UMBERTO I, NUMERO 41. DI CRIMINALISSIMA CARDENA' CONSULTING, BASATA A FALERONE, VIA MARIA MONTESSORI 6 63837 FALERONE - criminalissimo numero di telefono Tel: 0734.710786 - altro criminalissimo numero di telefono 3335915666, criminalissima e mail info@cardenaconsulting.it criminalissima email formazione@cardenaconsulting.it - P.IVA: 01840990442) E CRIMINALISSIMO BLOG VINCITORI E VINTI. IL BASTARDO MALAVITOSO PAOLO CARDENÀ, SEMPRE IN CRAVATTA STILE "COLLETTI LERCI", RICICLA SOLDI ASSASSINI DEI MEGA OMICIDA DI COSA NOSTRA, CRISAFULLI DI MILANO https://it.wikipedia.org/wiki/Crisafulli_(clan) )!!!SIMONA PREMOLI EX MARINA-BERLUSCONI-S LESBIAN-LOVERhttps://www.blogger.com/profile/07265505502915199728noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-33759600231462615122018-08-04T03:40:17.785-07:002018-08-04T03:40:17.785-07:003
AGAIN AND AGAIN AND AGAIN AND AGAIN...
L'IM...3<br />AGAIN AND AGAIN AND AGAIN AND AGAIN...<br /><br />L'IMMENSO PRENDI CAZZI IN CULO LUIGI BERLUSCONI (FIDANZATA-WIKIPEDIA-PADRE SPAPPOLA MAGISTRATI E SBAUSCIA TROIE POCO PIU' CHE BAMBINE, SILVIO BERLUSCONI..... " PER SEMPRE FUORI DAI COGLIONI") DI DI CRIMINALISSIMA FININVEST ALIAS (MA)FI(A)NINVEST, CRIMINALISSIMA MOLMED, CRIMINALISSIMA MOLMED SPA, CRIMINALISSIMA HOLDING ITALIANA QUATTORDICESIMA SPA (GIA' CASSAFORTE DI COSA NOSTRA: DI STEFANO BONTATE, PRIMA E TOTO RIINA, POI), CRIMINALISSIMA BANCA MEDIOLANUM MAFIOLANUM CAMORRANUM NDRANGOLANUM LAVALAVAPERCOCALEROSCOLOMBIANUM NAZISTANUM (OVE RICICLA SOLDI ASSASSINI A RAFFICA PROPRIO COME ACCADEVA NELLA SCHIFOSA, MALAVITOSA, DAVVERO BASTARDA BANCA RASINI DEL TOPO DI FOGNA LUIGI BERLUSCONI "NONNO"<br />http://susannaambivero.blogspot.com/2009/08/rasini-la-banca-di-berlusconi-e-della.html COME, D' ALTRONDE, NELLA MALAVITOSISSIMA FININVEST DEL SUO PEZZO DI MERDA PADRE, NOTO PEDOFILO SPAPPOLA MAGISTRATI SILVIO BERLUSCONI http://www.antimafiaduemila.com/home/primo-piano/68166-berlusconi-soldi-e-boss-mafiosi-negli-appunti-di-falcone.html ), CRIMINALISSIMA SOLDO LTD ROMA, CRIMINALISSIMA SOLDO FINANCIAL SERVICES LTD, CRIMINALISSIMA ELIGOTECH AMSTERDAM, CRIMINALISSIMA CGNAL DI TOPO DI FOGNA BERLUSCORROTTISSIMO MARCO CARRAI, CRIMINALISSIMA ALGEBRIS DI MEGA RICICLA SOLDI MAFIOSI DAVIDE SERRA ED ALTRA MERDA NAZIMAFIOSA BERLUSCONICCHIA VARIA STA CREANDO NUOVE OVRA E GHESTAPO DEL WEB!! COL PRIMA CITATO MERDONE BERLUSCONICCHIO MARCO CARRAI DI CGNAL, COL NAZI-ST-ALKER, ACCERTATO PEDERASTA INCULA BAMBINI, FREQUENTISSIMO MANDANTE DI OMICIDI, GIA' TRE VOLTE FINITO IN CARCERE: PAOLO BARRAI NATO A MILANO IL 28.6.1965 ( O FREQUENTISSIMO MANDANTE DI OMICIDI, GIA' TRE VOLTE FINITO IN CARCERE: PAOLO PIETRO BARRAI NATO A MILANO IL 28.6.1965 CHE SIA)!!! E SIA CHIARO, PLEASE: IO SONO MARIA GRAZIA CRUPI DI MILANO. SONO L'EX AMANTE LESBICA DI MARINA BERLUSCONI. GLI HO LECCATO LA FIGA E GLI HO MESSI AGGEGGI SESSUALI NEL DI DIETRO PER BEN 13 ANNI. SE VI E' UNA AMICA INTIMA DI LGBT QUELLA SONO PROPRIO IO. MA DEBBO URLARE UNA COSA, ADESSO: LUIGI BERLUSCONI PRENDE CAZZI DI 30 CM IN SU FINO ALLA PROSTATA, FA BOCCHINI SU BOCCHINI E BEVE LITRI SU LITRI DI SBORRA. E' UN OMOSESSUALE PERSO, PRESTO, MOLTO PROBABILMENTE, SI FARA' ANCHE LA OPERAZIONE E DIVERRA' TRANS!SIMONA PREMOLI EX MARINA-BERLUSCONI-S LESBIAN-LOVERhttps://www.blogger.com/profile/07265505502915199728noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-4284270863947536052018-08-04T03:40:00.874-07:002018-08-04T03:40:00.874-07:002
CIAO A TUTTI. SIMONA PREMOLI, EX AMANTE DI MARI...2<br /><br />CIAO A TUTTI. SIMONA PREMOLI, EX AMANTE DI MARINA BERLUSCONI PER BEN 13 ANNI ED EX AGENTE DELLA CIA IN DIVERSI PAESI DEL MONDO ( BERLUSCONIA, USA, PUERTO RICO, REPUBBLICA DOMINICANA, INGHILTERRA, SVIZZERA, ECT ECT).<br />https://twitter.com/premolisimona?lang=en<br />https://twitter.com/PremoliSimona/status/937885752003723265<br />https://twitter.com/premolisimona/status/876055837420158976<br />https://twitter.com/PremoliSimona/status/946915645756715009<br />https://twitter.com/PremoliSimona/status/946923968245784576<br />https://twitter.com/PremoliSimona/status/977570748847050754<br />https://plus.google.com/113646548587006228899<br />https://it.linkedin.com/pub/dir/Simona/Premoli<br />OLTRE CHE PORNOSTAR AMATORIALE DI ENORME SUCCESSO ( HO APPENA FINITO DI GIRARE A MIAMI IL MIO GRANDISSIMO NUOVO PORNO " LECCO LA FIGA DI MARINA BERLUSCONI, GIORNO E NOTTE, ANCHE NEI SUOI UFFICI DI (MA)FI(A)NINVEST". IN ANTEPRIMA MONDIALE, SI, MONDIALE, VI FACCIO VEDERE UNA FOTO DEL FILM.<br />http://it.cultura.linguistica.narkive.com/XV3Bw8gY/sono-simona-premoli-ex-amante-lesbica-di-marina-berlusconi-e-per-ben-13-anni-e-13-ani-che-mi-sono:i.1.1.thumb )<br />E SON PURE STATA PER TANTISSIMO TEMPO, COMPLICE, COLLUSA, STRETTISSIMO COLLABORATRICE DEL NEO PIDUISTA COME ME, NONCHE' MEGA RICICLA SOLDI DI MAFIE DI TUTTO IL MONDO: GIANPIERO SAMORÌ DEL CRIMINALISSIMO MOVIMENTO "MODERATI (MALAVITOSI) IN RIVOLUZIONE". ED ORA DICO BASTA A STA MERDA DI COSA NOSTRA, CAMORRA E NDRANGHETA FINANZIARIA CHE DA SEMPRE STI PEZZI DI MERDA BERLUSCONICCHI RAPPRESENTANO ( VI ASSICURO, SPESSO PURE PEDOFILI, STRAGISTI ED ASSASSINI, IN QUANTO ORDINANTI DOZZINE DI STRAGI E MIGLIAIA DI OMICIDI MASCHERATI DA FINTI SUICIDI, MALORI ED INCIDENTI, IL TUTTO VIA VARIE LORO LOGGE MASSONICHE OMICIDA....NE ERO DENTRO QUINDI SO' QUESTO ALLA PERFEZIONE PER AVERLO VISSUTO, NON SOLO VISTO... I BASTARDI ASSASSINI E STRAGISTI SILIVO BERLUSCONI ED ENNIO DORIS ORDINANO DOZZINE DI STRAGI E MIGLIAIA DI OMICIDI MASCHERATI DA FINTI SUICIDI, MALORI ED INCIDENTI, IL TUTTO VIA VARIE LORO LOGGE MASSONICHE KILLER, COME ANCHE ATTRAVERSO MAFIA, CAMORRA, NDRANGHETA, A CUI LAVANO MONTAGNE DI SOLDI ZUPPI DI SANGUE DI MORTI AMMAZATI, ED ANCOR PIU', ATTRAVERSO LORO SANGUINARIE NUOVE OVRA E GESTAPO, SIA PUBBLICHE CHE PRIVATE) .SIMONA PREMOLI EX MARINA-BERLUSCONI-S LESBIAN-LOVERhttps://www.blogger.com/profile/07265505502915199728noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-58615771707756566752018-08-04T03:39:22.396-07:002018-08-04T03:39:22.396-07:00SCHIFOSISSIMA PUTTANA FEDERICA FUMAGALLI (INSTAGRA...SCHIFOSISSIMA PUTTANA FEDERICA FUMAGALLI (INSTAGRAM): NON E' FIDANZATA DEL NOTO RICCHIONE LUIGI BERLUSCONI! ! LA FIDANZATA DEL SEMPRE SBORRATO IN CULO, LUIGI BERLUSCONI, E' UN MASSONE MAFIOSO CON LA BARBA! A MORTE IL MARKETING VISCIDO, FALSO E TRUFFATORE DI STAMPO BERLUSCONICCHIO!<br /><br />1<br /><br /><br />E' INFATTI SEMPRE SBORRATO DENTRO AL CULO: LUIGI BERLUSCONI! CON PADRE: IL DITTATORE NAZISTA E MAFIOSO, STRAGISTA SPAPPOLA MAGISTRATI, ASSASSINO MANDANTE DI CENTINAIA DI OMICIDI MASCHERATI DA FINTI SUICIDI, MALORI, INCIDENTI: PORCO PEDOFILO SILVIO BERLUSCONI!!!! E CON FIDANZATA: UN ^MASSONE MAFIOSO^ CON LA BARBA https://images-3662.kxcdn.com/fidelitynews/wp-content/uploads/2017/07/1499669813_59632533d5906.jpg?w=580<br />E NON LA NOTA PUTTANA, CHIAVATA DA MEZZA MILANO, IN MILLE CLUB PRIVE', FEDERICA FUMAGALLI ( CHE STA SOLO FACENDO FINTA DI STARE COL RICCHIONE FEMMINONE LUIGI BERLUSCONI, CHE QUI VEDETE, NON PER NIENTE, IN UNA FOTO, TUTTO DEPILATO, COSA TIPICA DEI CULACCHIONI SEMPRE SBORRATI DENTRO AL CULO https://static.fanpage.it/wp-content/uploads/sites/15/2016/01/prima-e-dopo-luigi-berlusconi.jpg ... FANNO FINTA, I DUE, DI STARE INSIEME, A SCOPO DI NAZIMAFIOSO TRUFFALDINO MARKETING, SOLITO CRIMINALE MODO DI COMUNICARE BERLUSCONICCHIO). DICEVO...HA SEMPRE MEGA CAZZI IN CULO, LUIGI BERLUSCONI. CON PADRE, IL DITTATORE FASCIONDRANGHETISTA, CHE HA ORDINATO LE STRAGI RIGUARDANTI GIOVANNI FALCONE E PAOLO BORSELLINO ( E DOZZINE DI ALTRE, QUALI TUTTE QUELLE FASCISTE DEGLI ANNI 70 ED 80 E PURE QUELLA DI BRINDISI). CHE HA ORDINATO CENTINAIA E CENTINAIA DI OMICIDI, FACENDOLI PASSARE PER FALSI INFARTI, SUICIDI O INCIDENTI. VIA SUE OVRA E GESTAPO ETERNAMENTE PIDUISTONE, SIA PUBBLICHE E PRIVATE. PRENDE ANCHE DUE CAZZI IN CULO ALLA VOLTA, LUIGI BERLUSCONI, CHE HA COME FIDANZATA, UN ^MASSONE MAFIOSO^ CON LA BARBA ( CHE SUI SLINGUA, DA RICCHIONE INFINITO, QUALE LUIGI BERLUSCONI, DA SEMPRE, ALTRO NON E' http://www.ilsussidiario.net/img/_THUMBWEB/luigi_berlusconi_thumb660x453.jpg ). SI, COME VEDETE IN QUESTA FOTO http://www.ilsussidiario.net/img/_THUMBWEB/luigi_berlusconi_thumb660x453.jpg , IL FEMMINONE SEMPRE CON CAZZI DI 30 CM IN CULO, LUIGI BERLUSCONI, SLINGUA UN ^MASSONE MAFIOSO^ DELLA MEGA ASSASSINA GRAN LOGGIA DEL DRAGO DEL "FORSE PRIMA CITATO" DITTATORE FASCIOMAFIOSO, STRAGISTA SPAPPOLA MAGISTRATI, MANDANTE DI MIGLIAIA DI OMICIDI MASCHERATI DA FINTI SUICIDI, MALORI, INCIDENTI, NOTO PEDOFILO SILVIO BERLUSCONI!!! DI CRIMINALISSIMA MEDIASET ALIAS MAFIASET, CAMORRASET, NDRANGASET, NAZISTSET. DI CRIMINALISSIMA FININVEST ALIAS (MA)FI(A)NINVEST. DI CRIMINALISSIMA MOLMED. DI CRIMINALISSIMA HOLDING ITALIANA QUATTORDICESIMA SPA (GIA' CASSAFORTE DI COSA NOSTRA DI STEFANO BONTATE PRIMA E TOTO RIINA, POI...CASPITERINA CHE SOCI PER BENE, CASPITERINA, WAGLIO'). DI CRIMINALISSIMA BANCA MEDIOLANUM MAFIOLANUM CAMORRANUM NDRANGOLANUM LAVALAVAPERCOCALEROSCOLOMBIANUM NAZISTANUM...COME PURE E STRA PURE...DI CRIMINALISSIMA SOLDO LTD ROMA. 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DI CRIMINALISSIMA ALGEBRIS DI MEGA RICICLA SOLDI MAFIOSI DAVIDE SERRA, PIU' DI ALTRA MERDA "FINANZIAR-CRIMINALE, FASCIOMAFIOSA, BERLUSCONICCHIA VARIA!<br />SIMONA PREMOLI EX MARINA-BERLUSCONI-S LESBIAN-LOVERhttps://www.blogger.com/profile/07265505502915199728noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-78189790497174959152018-05-28T05:15:43.238-07:002018-05-28T05:15:43.238-07:00Useful Information, your blog is sharing unique in...Useful Information, your blog is sharing unique information....<br />Thanks for sharing!!! <br /><a href="http://www.agtoolservices.com/" rel="nofollow">farm accounting and management services</a><br /><a href="http://www.agtoolservices.com/aboutus.html" rel="nofollow">best agricultural software supplier</a>Agtoolshttps://www.blogger.com/profile/10925167329306846143noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-25616477884115963692018-05-14T04:14:29.625-07:002018-05-14T04:14:29.625-07:00To start your own Bitcoin Exchange platform instan...To start your own Bitcoin Exchange platform instantly Online cryptocurrency exchanges <br /><br />software/script is there then you exchange cryptocurrencies for another digital currency >> <br /><br />click here <br /><a href="https://bitexchange.systems/" rel="nofollow">cryptocurrency exchange</a><br /><a href="https://bitexchange.systems/" rel="nofollow">software/script <br />bitcoin exchange software</a><br /><a href="https://bitexchange.systems/" rel="nofollow"><br />bitcoin exchange script</a><br />rajesh Kumarhttps://www.blogger.com/profile/10322087056067731502noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-56704801848001741022018-04-17T20:03:24.772-07:002018-04-17T20:03:24.772-07:00thank you for sharing
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I have never unde...Grad student in economics here.<br /><br />I have never understood why mathematics was way too important in economics. If you do not take additional math classes from math department during your undergrad years, you are screwed. You will not be able to get into a decent phd program. Suppose that you have entered into a phd program and you are a possible candidate for becoming a brilliant social scientist, with a great intuition and grasp, but unable to demonstrate some proofs in your prelims, you will be get kicked out from the program. But I think, there is no penalty for any academic who is manipulating or overselling mathematical models.<br /><br />I need to quote George Box: "All models are wrong, some are useful". In contemporary economics, all models are wrong and nothing is useful.<br /><br />By the way, I think we need a blog post about your precious advices for prospective students (for phd applicant and JMCs)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-29251460096596866402018-02-08T22:55:11.814-08:002018-02-08T22:55:11.814-08:00Hey Chris,
If their main point is that populati...Hey Chris,<br /><br /> If their main point is that population density will not be a decent proxy for income in a Malthusian world, why do the first two lines of the abstract read "Among countries colonized by European powers during the past 500 years, those that were relatively rich in 1500 are now relatively poor. We document this reversal using data on urbanization patterns and population density, which, we argue, proxy for economic prosperity."<br /><br /> Seems pretty clear.<br /><br /> Sure, they acknowledge a caveat that, in their Malthusian model, there are two opposing forces. But without the unrealistic assumption highlighted in my post, there won't be two opposing forces. Population density won't proxy prosperity period. This is why hunter-gatherers are often recorded as having higher incomes than settled agrarian societies. <br /><br /> Best,<br /> Doug<br /><br /> <br /><br /> <br /><br />Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-22189125609024635902018-02-08T12:50:03.481-08:002018-02-08T12:50:03.481-08:00Hi Doug,
You claim that the point they are making...Hi Doug,<br /><br />You claim that the point they are making is "population density will be a decent proxy for income in a Malthusian model." The point they are making is explicitly the exact opposite: that "caution is required in interpreting population density as a proxy for income per capita." This, as their little, pedagogical model shows, is at least in part because of simultaneous causality between income and population. They are not simply focusing on the equilibrium steady-state relationship, you are taking the quote about variance in technology and the induced positive association between income and population density out of context.<br /><br />Further, as I keep saying, the point they're making doesn't hinge on the goofy assumption you highlight. For example, consider what happens if we rewrite equation (2) as an AR(1) process in the log rather than the level of population density. We still get a positive association between income and density across steady-states if we assume that all that's driving variation across countries is variation in technology, but this slightly different specification does not have the problem you highlight. <br /><br />The point, as I say above, is that it doesn't really matter. They're not taking this model directly to data, they're just using it to make a simple point about identification in this context, and it's not the point you claim they're making. It would also, as I noted, be a point which would be extremely difficult to make if they couldn't use mathematics to express the argument.<br /><br />Chris.<br /><br />Chris Ahttps://www.blogger.com/profile/15553934787026424150noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-53237150505280429632018-02-08T12:34:27.276-08:002018-02-08T12:34:27.276-08:00Here's another tweet from Chris: "Again, ...Here's another tweet from Chris: "Again, the basic point Acemoglu et al are making, which you're misconstruing, is robust to that assumption. This is not "bullshit" math being used to "trick people," particularly the "feebleminded." These are remarkable, uncharitable, and wrong, claims. Dear Lord, indeed."<br /><br />My response: Chris -- have another look at the model. If you set rho = 1, you get back to the classic Malthusian model, where there is no correlation between income and population density. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-21902534629399474902018-02-08T12:30:14.514-08:002018-02-08T12:30:14.514-08:00This comment has been removed by the author.Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-4995758436824588522018-02-08T10:58:23.609-08:002018-02-08T10:58:23.609-08:00Chris -- if you really want to show me up, the way...Chris -- if you really want to show me up, the way you can do it is by showing with algebra that the positive steady state relationship between income and population doesn't actually hold in this model. This would prove I'm wrong once and for all. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-25973955382778396992018-02-08T10:54:44.528-08:002018-02-08T10:54:44.528-08:00Chris replies again on twitter: "Again, Doug,...Chris replies again on twitter: "Again, Doug, you're entirely missing the point of the model, which is that there's an "identification problem," as the authors put it---they're not limiting attention to SS. Their point is precisely the opposite of the claim you appear to think they're making, see last par. p10."<br /><br />Response: Dear Lord Chris. For the last time, I'm taking issue with the positive steady state relationship between population and income, and the fallacious assumption which yields it.<br /><br />The point I think they are making with the model is that there is good reason to think that population and income will be positively correlated in a Malthusian economy. I'm saying, this comes from a bad assumption. Correct that assumption, and this positive SS relationship doesn't hold, and thus, there is no reason to think income and population will be correlated in a Malthusian world. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-49576681021755212232018-02-08T10:21:09.812-08:002018-02-08T10:21:09.812-08:00Chris replies again: "Nope, you misunderstood...Chris replies again: "Nope, you misunderstood the key piece of logic, which is that even assuming there's a positive causal effect of income on pop. density, we could observe any association between those outcomes. It isn't those three MIT profs (and me) who are confused by this model...."<br /><br />Hate to sound like a broken record here Chris, but, once again, we're talking about the steady state. In the steady state, there is, in fact, necessarily a positive relationship between p* and y* in their model (just not in real life). Yes, I realize that out of the SS a different relationship could materialize. However, I actually would like to defend AJR here -- differences in technology were enormous between hunter-gatherer groups and agricultural groups in the Americas, so that, even away from the SS, differences in A were likely to be dominant. Thus, given their model, applying it to data, while not perfect, is not necessarily without reason. The problem is about the model, and particularly with the SS relationship. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-62017291698088192362018-02-08T10:15:48.244-08:002018-02-08T10:15:48.244-08:00On twitter, Chris replies again: "Yes, if onl...On twitter, Chris replies again: "Yes, if only A varies, that's so. And if only epsilon varies, there will be a negative association! The point, as they say, is that there's an identification problem. You have yet again just pulled one equation out of a sim. system and drawn erroneous conclusions."<br /><br />My response: OK, but in the blog post, it's clear I'm talking about the steady state. I don't see how pointing out that, outside of the steady state, things are different refutes the steady state positive relationship between p* and y*. It's this positive SS relationship which I take issue with. You seem to be saying that this positive steady state relationship between p* and y* is valid. However, I'm saying it's counterfactual, and comes from a specific, invalid assumption in AJR. <br /><br /><br /><br /><br /><br /><br /><br />Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-1035146111593016752018-02-08T07:24:34.846-08:002018-02-08T07:24:34.846-08:00Economath could be useful but one have to be very ...Economath could be useful but one have to be very wary of the model limitations which are often dismissed.<br /><br />Finally, Economath need to be supported by Econostat. Your model need to support the observed data and be estimated via ecnometric analysis. So many models, including many DESG models, fail this tests and should only be taken as incomplete theory and interesting exercise.Philippe Marcilhttps://www.blogger.com/profile/01040870749107318765noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-62127926591718842662018-02-08T00:26:34.692-08:002018-02-08T00:26:34.692-08:00On twitter, Chris replies: "That's not ri...On twitter, Chris replies: "That's not right and not what they say. Again, the model says income and population are sim. determined, but you are taking the implications of equation (2) in isolation. Eq (1) says higher pop -> lower income. In data, sign of corr. depends on what is varying across countries."<br /><br />First, Chris is quite correct that I did not present the full model above, only the offending bit of logic. However, you can plug in for p* in the equation above using the production function, set y-bar to zero for simplicity, and then, I hope, you'd find truth to AJR's claim that "As long as ρ < 1, there will be a steady-state level of income per capita, y∗, and steady state<br />population density, p∗, both strictly increasing in productivity A." It does seem to me that Chris is speaking away from the steady-state, in which his argument sounds quite correct. However, in the steady state, I actually buy AJR's argument. <br /><br />Let's suppose Chris is correct here that AJR are wrong, and that an editor of Econometrica and tenured professors at MIT themselves did not even understand the implications of a very simple model. Does this make the use of math look better? Or, instead, if Chris, a tenured economics professor, is wrong and AJR are right, doesn't this anecdote also provide a cautionary tale about how tricky even a simple mathematical model can be? <br />Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-22944283558100983002018-02-07T20:29:16.236-08:002018-02-07T20:29:16.236-08:00I actually do think that the intentions of these r...I actually do think that the intentions of these researchers were pure. I suspect they actually do believe that this algebra allowed them to overturn a basic result of the classic Malthusian model. But, math was still a tool in this case for an elaborate self-deception. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-73259128575402621542018-02-07T12:44:53.672-08:002018-02-07T12:44:53.672-08:00"Math in this case is used as little more tha..."Math in this case is used as little more than a literary device designed to fool the feebleminded."<br /><br />That's a pretty striking assumption of motive on the part of Acemoglu et al. What's your reason for thinking that they were out to fool people? JPGhttps://www.blogger.com/profile/02632504264072261599noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-87971656794655134092018-02-07T12:34:12.387-08:002018-02-07T12:34:12.387-08:00Well, if I had to assign importance, I would of co...Well, if I had to assign importance, I would of course have to say that signalling is dominant, as it is in most spheres, and second acknowledge the usefulness of math, and put subterfuge third. Note that, in fact, most economists actually are pure-hearted. They are generally innocent of any knowledge that they do so much math simply to signal, and they aren't lying on purpose. What also happens is an elaborate self-deception, which takes place with purely empirical researchers as well. Doug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-74096843270168826542018-02-07T12:26:10.841-08:002018-02-07T12:26:10.841-08:00So... economics grad students do lots of math so t...So... economics grad students do lots of math so they can learn how to lie better?<br /><br />I thought so, and that's why I'm transferring to a useful social science... Geography. I Will Never Accept The Terms of Servicehttps://www.blogger.com/profile/09422355923256894207noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-487360320987250872018-02-07T12:25:16.022-08:002018-02-07T12:25:16.022-08:00Hey Chris -- thanks for your post. I encourage you...Hey Chris -- thanks for your post. I encourage you to take a second look at the model above! If you impose a steady state, population is indeed increasing in income. And that is, in fact, a (wrong!) prediction about the data. Economath has struck again!<br /><br />All the best,<br />DougDoug Campbell https://www.blogger.com/profile/11028049845008665877noreply@blogger.comtag:blogger.com,1999:blog-4409551172339639840.post-90398061397409209852018-02-07T11:11:45.331-08:002018-02-07T11:11:45.331-08:00The model in the working paper version of the pape...The model in the working paper version of the paper is there for a simple reason: to consider the implications of a *simultaneous* relationship between population and income. It is *not* true in this model that "population density (which is proportional to technology) will be proportional to income!" That claim is analogous to taking the demand equation out of a supply and demand model and claiming the model implies that we should see lower quantities traded in times and places where prices are higher. <br /><br />The equation in the post above is meant to capture the Malthusian notion that higher income causes higher population growth. The other equation in the model---which is important if we want to solve the model--- captures causality running in the other direction. That equation doesn't just say "income which is proportional to technology," it says<br /><br />y(t) = A p^{-\theta},<br /><br />which, for \theta>0, captures a negative causal effect of population density on income, a mechanism operating through diminishing returns to land, in this story. <br /><br />The observed relationship between income and population density can't be read off either of these equations alone. A more stylized version of their argument might run:<br /><br />population = f ( income, shocks )<br /><br />income = g( population, technology, shocks ),<br /><br />which means in part that either technology shocks or population shocks play out over time as changes in both income and population.<br /><br />It is true that the way expressed the first equation, their model makes absurd predictions about population growth rates. But it doesn't really matter, as they're just using the model to make the point above, not directly taking it to data, and the model could be easily rewritten in such a way as to address this problem without changing the point.<br /><br />Finally, note that the "economath" did exactly as it's supposed to do in this case: forced us to specify precisely the assumptions we need to make, and highlights where those assumptions may lead us astray. If these same arguments were expressed verbally, all of this would be much more opaque.<br /><br />I don't know, but I would guess that the model was removed from the publication version not because of this "mistake," but rather because it takes two pages of space elaborating on the idea that the relationship between population density is not as simple as Malthus predicted, but then goes ahead in the empirical work to largely, in contrast to what their model says, take population density as a proxy for income! Which is an actual problem with the analysis, but one dutifully highlighted in the paper.<br /><br />Chris.<br /><br /><br />Chris Ahttps://www.blogger.com/profile/15553934787026424150noreply@blogger.com