Lars P. Syll

Policy evaluation and the hazards to external validity As yours truly has repeatedly argued on this blog (e.g. here here here),  RCTs usually do not provide evidence that their results are exportable to other target systems. The almost religious belief with which many of its propagators portray it, cannot hide the fact that RCTs cannot be taken for granted to give generalizable results. That something works somewhere is no warranty for it to work for us or...

Regression analysis and randomisation distract us from the real scientific issues  In my view, regression models are not a particularly good way of doing empirical work in the social sciences today, because the technique depends on knowledge that we do not have. Investigators who use the technique are not paying adequate attention to the connection – if any – between the models and the phenomena they are studying. Their conclusions may be valid for the...

A meta-analysis identifies a set of studies, each of which provides one or more estimates of the effect of some intervention. For example, one might be interested in the impact of job training programs on prisoner behavior after release. For some studies, the outcome of interest might be earnings; do inmates who participate in job training programs have higher earnings after release than those who do not? For other studies, the outcome might be the number of weeks employed...

Formalized economics bordering on the insane What guarantee is there … that economic concepts can be mapped unambiguously and subjectively – to be terribly and unnecessarily mathematical about it – into mathematical concepts? The belief in the power and necessity of formalizing economic theory mathematically has thus obliterated the distinction between cognitively perceiving and understanding concepts from different domains and mapping them into each other....

Ljus i mörkret (personal) I dessa tider — när ljudrummet dränks i den kommersiella radions  pubertalflams — har man nästan gett upp. Men det finns ljus i mörkret. I programmet Text och musik med Eric Schüldt — som sänds på söndagsförmiddagarna i P2 mellan klockan 11 och 12 — kan man lyssna på seriös musik och en programledare som verkligen har något att säga. I dag kunde man bland annat höra filmmusik av vår egen Stefan Nilsson, vars musik till Ingmar...

The need for a new economics curriculum without the present suicidal formalism When the global economy crashed in 2008, the list of culprits was long, including dozy regulators, greedy bankers and feckless subprime borrowers. Now the dismal science itself is in the dock, with much soul-searching over why economists failed to predict the financial crisis. One of the outcomes of this debate is that economics students are demanding the reform of a curriculum...

Hemstadens poet har lämnat oss En man har gått ur tiden. Och en stad har mist sin store poet. Jacques Werup (1945-2016). Det var en match mellan MFF och HIF, arvfienden från Helsingborg, årets match. Jag var knappt tio år och MFF kunde för mig ‘aldrig’ förlora. Men HIF ledde med 2-0 en halvtimme in i andra halvlek, ‘Kajan’ stod i mål för ‘di blåe’, Tore Svensson hade blivit skadad och på den tiden fanns inga nya spelare att ta in. Kalle Svensson i HIF-målet...

Mathematics and statistics do not solve our disagreements Statistical Science is not really very helpful for understanding or forecasting complex evolving self-healing organic ambiguous social systems – economies, in other words. A statistician may have done the programming, but when you press a button on a computer keyboard and ask the computer to find some good patterns, better get clear a sad fact: computers do not think. They do exactly what the...

The significance of insignificance (wonkish) Skewness, outliers, multiple hypothesis testing, and reliance on asymptotics often — as is well-known among most statisticians — give rise to spurious findings. But the problem may actually be even worse than we have thought. In an interesting new paper, Alwyn Young, after having looked at over 2000 regressions reported in American Economic Association journals, summarizes his findings: Armed with an idea and...

RCTs — the illusion of assumption-free learning Blinding is rarely possible in economics or social science trials, and this is one of the major differences from most (although not all) RCTs in medicine, where blinding is standard, both for those receiving the treatment and those administering it … Subjects in social RCTs usually know whether they are receiving the treatment or not and so can react to their assignment in ways that can affect the outcome...