Lars P. Syll

Monte Carlo simulations — no substitute for thinking In some fields—physics, geophysics, climate science, sensitivity analysis, and uncertainty quantification in particular—there is a popular impression that probabilities can be estimated in a ‘neutral’ or ‘automatic’ way by doing Monte Carlo simulations: just let the computer reveal the distribution … Setting aside other issues in numerical modeling, Monte Carlo simulation is a way to substitute...

Selling deaf aids … .[embedded content]

In econometrics one often gets the feeling that many of its practitioners think of it as a kind of automatic inferential machine: input data and out comes causal knowledge. This is like pulling a rabbit from a hat. Great, but as renowned statistician David Freedman had it, first you must put the rabbit in the hat. And this is where assumptions come into the picture. The assumption of imaginary ‘superpopulations’ is one of the many dubious assumptions used in modern...

Model uncertainty and ergodicity Post Keynesian authors have offered various classifications of uncertainty … A common distinction is that of epistemological versus ontological uncertainty, with the former depending on the limitations of human reasoning and the latter on the actual nature of social systems … Models of ontological uncertainty tend to hinge on the existence of information that is critical to the decision-making task. Fundamental...

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Weekend combinatorics work problem (IV) When my daughter (who studies mathematics) and yours truly solve a combinatorics problem together it takes 12 minutes. If my daughter tries to solve the problem herself it takes her 10 minutes more than it takes when I solve it alone. How long does it take me to solve the problem?

Nyligen höjde Riksbanken återigen styrräntan. Förhoppningen är att de ökade räntekostnaderna ska dämpa efterfrågan och inflationsförväntningarna och därmed leda till en lägre inflation. Men räntehöjningar kommer sannolikt inte lösa inflations­problemen. Däremot riskerar de att allvarligt skada den ­svenska samhällsekonomin. De ökade konsumentpriserna beror inte på låga räntor utan primärt på flaskhalsar från pandemin, ökade energi- och matpriser från kriget i Ukraina, att...

Göte Kildén In Memoriam En av den svenska arbetarrörelsens stora kämpar, Göte Kildén, har gått ur tiden. Göte var i slutet på 1960-talet med och grundade den svenska sektionen av Fjärde Internationalen och var partiordförande i Socialistiska Partiet fram till 1991. I tjugofem år arbetade han  på Volvo Lastvagnar och ledde facklig opposition inom Metall.  Vila i frid min vän. [embedded content]

The misuse of mathematics in economics Many American undergraduates in Economics interested in doing a Ph.D. are surprised to learn that the first year of an Econ Ph.D. feels much more like entering a Ph.D. in solving mathematical models by hand than it does with learning economics. Typically, there is very little reading or writing involved, but loads and loads of fast algebra is required. Why is it like this? … One reason to use math is that it is...

DSGE models — a macroeconomic dead end Both approaches to DSGE macroeconometrics (VAR and Bayesian) have evident vulnerabilities, which substantially derive from how parameters are handled in the technique. In brief, parameters from formally elegant models are calibrated in order to obtain simulated values that reproduce some stylized fact and/or some empirical data distribution, thus relating the underlying theoretical model and the observational...