This paper defines and studies a variable selection procedure called Testing-Based Forward Model Selection. The procedure inductively selects covariates which increase predictive accuracy into a working statistical regression model until a stopping criterion is met. The stopping criteria and selection criteria are defined using statistical hypothesis tests. The paper explicitly describes a testing procedure in the context of high-dimensional linear regression with heteroskedastic disturbances. Finally, a simulation study examines finite sample performance of the proposed procedure and shows that it behaves favorably in high-dimensional sparse settings in terms of prediction error and size of selected model.
What determines risk-bearing capacity and the amount of leverage in financial markets? Using unique archival data on collateralized lending, we show that personal experience can affect individual risk-taking and aggregate leverage. When an investor syndicate speculating in Amsterdam in 1772 went bankrupt, many lenders were exposed. In the end, none of them actually lost money. Nonetheless, only those at risk of losing money changed their behavior markedly; they lent with much higher haircuts. The rest continued largely as before. The differential change is remarkable since the distress was public knowledge. Overall leverage in the Amsterdam stock market declined as a result.
To reduce poverty and food insecurity in Africa requires raising productivity in agriculture. Systematic use of fertilizer and hybrid seed is a pathway to increased productivity, but adoption of these technologies remains low. We investigate whether the quality of agricultural inputs can help explain low take-up. Testing modern products purchased in local markets, we find that 30% of nutrient is missing in fertilizer, and hybrid maize seed is estimated to contain less than 50% authentic seeds. We document that such low quality results in low average returns. If authentic technologies replaced these low-quality products, however, average returns are high. To rationalize the findings, we calibrate a learning model using data from our agricultural trials. Because agricultural yields are noisy, farmers’ ability to learn about quality is limited and this can help explain the low quality equilibrium we observe, but also why the market has not fully collapsed.
Most models of ambiguity aversion satisfy Anscombe-Aumann’s Monotonicity axiom. Monotonicity imposes separability of preferences across events that occur with unknown probability. We construct a test of Monotonicity by modifying the Allais paradox to a setting with both subjective and objective uncertainty. Two experimental studies are conducted: while study 1 uses U.S. online workers and a natural source of ambiguity, study 2 employs European students and an Ellsberg urn. In both studies, modal behavior violates Monotonicity in a specific, intuitive way. Overall, our data suggest that violations of Monotonicity are as prevalent as violations of von Neumann-Morgenstern’s Independence axiom.
Le origini tra Umbria e Sicilia con Lino Leonardi 16 maggio 2017 - 18.00 - Studio 2 RSI, Lugano-Besso Ciclo prodotto da RSI Rete Due in collaborazione con l'Istituto di studi italiani. Otto incontri aperti al pubblico, viaggiando tra luoghi e regioni, al fianco dei protagonisti della nostra storia ...
ore 10.00 aula magna, campus di Lugano Apertura della cerimonia Boas Erez, Rettore dell Università della Svizzera italiana Saluto di benvenuto Monica Duca Widmer, Presidente del Consiglio dell Università della Svizzera italiana Intervento Boas Erez, Rettore dell Università della Svizzera ...
LEZIONI DI ARCHITETTURA Una serie di conferenze per raccontare al pubblico il lavoro di notevoli architetti e storici provenienti da continenti e ambiti culturali differenti: Amsterdam/Muharraq, Zurigo, Londra, Parma e Rio de Janeiro. La rassegna conferma la vocazione internazionale e multiculturale ...
Biblioteca dell'Accademia di architettura ArchiLetture Silvano Zorzi e l archivio fotografico della INCO s.p.a. La struttura ideale martedì 09 maggio 2017 ore 18.30 Biblioteca dell'Accademia Via Turconi CH-6850 Mendrisio
We test the effectiveness of self-help peer groups as a commitment device for precautionary savings, through two randomized field experiments among 2,687 microentrepreneurs in Chile. The first experiment finds that self-help peer groups are a powerful tool to increase savings (the number of deposits grows 3.5-fold and the average savings balance almost doubles). Conversely, a substantially higher interest rate has no effect on most participants. A second experiment tests an alternative delivery mechanism and shows that effects of a similar size can be achieved by holding people accountable through feedback text messages, without any meetings or peer pressure.
