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Minsky: Latest News

Rus­sell Stan­dish has been work­ing on Min­sky thanks to the extra funds raised by the donate but­ton below.

He has pro­duced a beta which is a sub­stan­tial improve­ment over the release ver­sion cur­rent­ly on the Source­forge home page. It adds:

• an equa­tion viewer–so you can design a mod­el and instant­ly see the equa­tions behind it from with­in Min­sky (as well as export them to LaTeX);
• A dif­fer­en­tial oper­a­tor, so you can cal­cu­late rates of change (and in typ­i­cal Rus­sell style, this is no ordi­nary numer­i­cal approx­i­ma­tion but a full sym­bol­ic dif­fer­en­tial sys­tem, so the approx­i­ma­tion prob­lems that apply with (to my knowl­edge) all oth­er sys­tem dynam­ics pro­gram dif­fer­en­tial oper­a­tors don’t apply to Min­sky);
• A large num­ber of bug fix­es.

With the caveat that beta ver­sions almost always have bugs, this ver­sion is very close to a new release can­di­date and I would rec­om­mend using it rather than the sta­ble release:

Min­sky Beta Page

Keep Russell Standish coding Minsky

Min­sky has been devel­oped thanks to two grants: an ini­tial US$128,000 grant from INET, and crowd­fund­ing of $78,000 from Kick­starter. With oth­er amounts from indi­vid­ual donor, that has fund­ed about 2500 hours of pro­gram­ming by the bril­liant pro­gram­mer behind Min­sky, Pro­fes­sor Rus­sell Stan­dish. I will be apply­ing for oth­er grants now that I am based in the UK, but in the mean­time more fund­ing is need­ed to keep the devel­op­ment rolling and to reserve Rus­sel­l’s skills for Min­sky. So please donate via the Pay­pal link above: the funds go direct­ly to Rus­sell, and the mon­ey raised so far–about $8,000–has helped pro­duce the lat­est beta, which

Source­Forge Project of the Month for Jan­u­ary 2014

We’re delight­ed that Source­Forge has seen fit to make Min­sky it’s Project of the Month. Min­sky is both a gen­er­al pur­pose sys­tem dynam­ics pro­gram, and the first such pro­gram specif­i­cal­ly designed to sup­port the build­ing of mon­e­tary mod­els of the econ­o­my.

Our design objec­tive has been to make it as intu­itive as pos­si­ble to use, while sup­port­ing var­i­ous advanced features–such as main­tain­ing con­sis­ten­cy between mul­ti­ple mon­e­tary flow tables–in as seam­less a way as pos­si­ble. We hope that users will find it use­ful, and we would be delight­ed to get cod­ing assis­tance from devel­op­ers, user assis­tance in bug test­ing and build­ing the help sys­tem, etc.

Dr. Rus­sell Stan­dish and I have been work­ing on Min­sky now for almost two years now–first using a $125K from INET’s Spring 2011 grant round and then anoth­er $80K from a suc­cess­ful Kick­starter cam­paign: Rus­sell as builder (cod­ing in C++ and Tcl/Tk) and me as archi­tect (play­ing with each release, spot­ting bugs and sug­gest­ing fea­tures). It’s been a part-time endeav­or: Rus­sell, as a con­tract pro­gram­mer, has to keep more than one iron in the fire, while I have a fair few balls in the air myself. Rus­sell has put in about 2000 hours of cod­ing over that time.

That amount of cod­ing is chick­en feed com­pared to the mil­lions of hours that have gone into a stan­dard com­mer­cial prod­uct like Microsoft Word or Excel, so Min­sky is still rough at the edges, and lacks a num­ber of fea­tures that you would expect in a com­mer­cial pack­age. But there is enough core func­tion­al­i­ty and sta­bil­i­ty in place for a first major release–the “Mun” ver­sion which can now be down­loaded from Source­Forge (major iter­a­tions of Min­sky are named after major thinkers in economics–we start­ed with Aris­to­tle).

There is still only a rudi­men­ta­ry and incom­plete Help file (did I say I had too many balls in the air?), so to make up for it I’ve record­ed the fol­low­ing set of 15 videos that cov­er most of the fea­tures of the pro­gram. They’re all up on YouTube (where the num­ber is the series changes from 8 to 11 to 15…), but here they are for easy ref­er­ence, with some notes about what each video cov­ers. All the Min­sky (mky) files used in the pre­sen­ta­tions are in this Zip file.

So if you’re into eco­nom­ic mod­el­ing and you’d like to devel­op dynam­ic mon­e­tary mod­els, Min­sky now has enough fea­tures to be worth using–and it won’t face the lim­i­ta­tions that apply to more con­ven­tion­al sys­tem dynam­ics pro­grams, like Stel­la, Ven­sim, Vis­sim, etc., that make it inher­ent­ly chal­leng­ing to mod­el the finan­cial sys­tem. With Min­sky and its God­ley Tables, mon­e­tary mod­el­ing is a cinch (and it will get eas­i­er as we add more capa­bil­i­ties to the pro­gram). So please, down­load the pro­gram, join our beta-test­ing group, and start build­ing mon­e­tary macro­eco­nom­ics.

If you’re a devel­op­er with time to devote to this project, imme­di­ate needs include:

• Spruc­ing up plots;
• Copy and paste sup­port files;
• Mul­ti­ple files open at once;
• Build­ing a LaTeX view­er into Min­sky;

Medi­um term needs include:

• A direct LaTeX edi­tor with seam­less trans­fer between the equa­tion pane and the can­vas pane;
• Adding Social Account­ing Matrix sup­port for equa­tion con­sis­ten­cy check­ing;

The long term objec­tives include:

• Trans­form a “scalar” eco­nom­ic mod­el into a “vec­tor” with mon­e­tary and phys­i­cal input-out­put dynam­ics with one click;
• Mul­ti­ple econ­o­my sup­port with finan­cial and phys­i­cal flows between economies, cur­ren­cy con­ver­sion, etc.;
• Data import­ing, manip­u­la­tion and non­lin­ear para­me­ter fit­ting

Minsky 1.0 Demo #1 Basics And Godley Table

Installing Min­sky from a ZIP file, the can­vas, wiring to build equa­tions, installing a graph, graph­ing a basic func­tion like sin(t), out­putting the equa­tions to LaTeX (which you can import into MathType in Word), and a basic “endoge­nous mon­ey” God­ley Table.

Min­sky Files: sine.mky (using Min­sky to plot a sine wave); Godley.mky (a basic pure­ly mon­e­tary mod­el, with no simulation–just the dou­ble-entry book­keep­ing table).

Minsky 1.0 Demo #2 Godley Simulation

Using a God­ley Table to define a numer­i­cal sim­u­la­tion: right-click to copy flows and vari­ables (“stocks”), defin­ing mon­e­tary equa­tions, and run­ning a sim­u­la­tion.

Min­sky file: GodleySim01.mky (the same mod­el as in the pre­vi­ous video with def­i­n­i­tions of flows added so that it can be numer­i­cal­ly sim­u­lat­ed).

Minsky 1.0 Demo #3 Godley-Goodwin Integration

Using time lags, enter­ing Greek char­ac­ters and sub­scripts, build­ing a dynam­ic mod­el using the flow­chart part of the pro­gram, using inte­gra­tion blocks in dynam­ic mod­els, mak­ing x‑y graphs as well as graphs of vari­ables against time.

Min­sky file: GodleySim02.mky (the same mod­el as in the pre­vi­ous video, but using time con­stants rather than arbi­trary num­bers for sys­tem para­me­ters); GodleyGoodwin01 and GodleyGoodwinSim01 (adding a Good­win mod­el of pro­duc­tion using the flow­chart aspects of the pro­gram, and adding XY charts, slow­ing down the sim­u­la­tion speed)

Minsky 1.0 Demo #4 Godley-Goodwin Integration

Start­ing to inte­grate a mon­e­tary and a phys­i­cal mod­el, using slid­ers to vary para­me­ters dur­ing a sim­u­la­tion.

Min­sky files: GodleyGoodwinSimInt01 (begin­ning to inte­grate the two mod­els: mak­ing the wage a mon­e­tary phe­nom­e­non)

Minsky 1.0 Demo #5 Godley Goodwin Integration #2

Doing it right: start­ing by mod­i­fy­ing the real cycli­cal mod­el to include mon­e­tary vari­ables.

Min­sky files: GodleyGoodwinSimInt01C (adding Price to the Good­win mod­el before attempt­ing the inte­gra­tion).

Minsky 1.0 Demo #6 Godley-Goodwin Integration

Con­tin­u­ing the process.

Min­sky files: GodleyGoodwinSimInt01D (com­plet­ing the inte­gra­tion)

Minsky 1.0 Demo #7 Godley-Goodwin Integration #4

Con­tin­u­ing the process.

Min­sky files include GodleyGoodwinSimInt03, where I add a lin­ear invest­ment func­tion to the lin­ear wage change func­tion that is the core of the Good­win mod­el.

Minsky 1.0 Demo #8 Godley-Goodwin Integration #5

Get­ting cycles in the mon­e­tary econ­o­my as well as the phys­i­cal. Intro­duc­ing an invest­ment func­tion as well as a wage change func­tion. Show­ing the debt-defla­tion mod­el.

Min­sky files include DebtDeflation02, which is the mon­e­tary ver­sion of my 1995 debt-cri­sis mod­el in “Finance and Eco­nom­ic Break­down”

Minsky 1.0 Demo #09 Multiple Godley Tables

Com­bin­ing MMT and MCT with two God­ley Tables, one for the Cen­tral Bank, the oth­er for Pri­vate Banks. Min­sky’s built-in log­ic to main­tain con­sis­ten­cy between assets and lia­bil­i­ties across mul­ti­ple God­ley Tables. A poten­tial­ly sur­pris­ing result about the rela­tion­ship between the change in pri­vate debt and the change in pub­lic debt.

Min­sky files: MinskyOnePointZeroDemo09MultipleGodleyTables (com­bines MMT and MCT and shows that the change in pri­vate debt and the change in pub­lic debt are not of equal and oppo­site mag­ni­tudes in a closed econ­o­my).

Minsky 1.0 Demo #10 Zooming

Group­ing enti­ties, zoom­ing in to see a group, edit­ing a group, using the Lorenz Strange Attrac­tor as first exam­ple, and my mod­el of debt-defla­tion as the sec­ond.

Minsky 1.0 Demo #11 Bugs

Bugs and how to cope with them.

Minsky 1.0 Demo #12 Lorenz model

Using the flow­chart side of the pro­gram to build the famous Lorenz mod­el. Chang­ing the Runge-Kut­ta para­me­ters to get a smoother sim­u­la­tion. Set­ting ranges on a graph.

Minsky 1.0 Demo13 # Lorenz model with Sliders

Using slid­ers to vary para­me­ters in a mod­el while it runs.

Min­sky files: Vari­a­tions on Lorenz, espe­cial­ly LorenzWithSliders02.

Minsky 1.0 Demo #14 Competitors

How does Min­sky stack up as a sys­tem dynam­ics pro­gram com­pared to the estab­lished play­ers Simulink, Ven­sim, and Vis­sim? It does­n’t have the pow­er of these estab­lished pro­grams of course–matching the fea­ture set of even Ven­sim would require tens thou­sands more hours of pro­gram­ming time, let alone that of Vis­sim or the mar­ket leader Simulink. But on a user-friend­li­ness scale, I think it’s easy to see that Min­sky is much eas­i­er to use than Ven­sim, sig­nif­i­cant­ly eas­i­er than Simulink, and with­in reach of Vissim–though it lacks some basic edit­ing fea­tures.

Minsky 1.0 Demo #15 Why Godley Tables?

This is the clinch­er. If you want to mod­el mon­e­tary dynam­ics, there is no oth­er pro­gram that offers any­thing like the God­ley Table for mod­el­ing the dou­ble-entry flows that char­ac­ter­ize the finan­cial sys­tem. A flow­chart is an inher­ent­ly weak tool for build­ing a mon­e­tary mod­el..