The classical Heckman (1976, 1979) selection correction estimator (heckit) is misspecified and inconsistent if an interaction of the outcome variable and an explanatory variable matters for selection. To address this specification problem, a full information maximum likelihood estimator and a...

The classical Heckman (1976, 1979) selection correction estimator (heckit) is misspecified and inconsistent if an interaction of the outcome variable and an explanatory variable matters for selection. To address this specification problem, a full information maximum likelihood estimator and a...

We analyse pricing, effort and tipping decisions in the online service Google Answers. While users set a price for the answer to their question ex ante, they can additionally give a tip to the researcher ex post. In line with the related experimental literature we find evidence that tipping is...

The classical Heckman (1976, 1979) selection correction estimator (heckit) is misspecified and inconsistent, if an interaction of the outcome variable with an explanatory variable matters for selection. To address this specification problem, a full information maximum likelihood (FIML) estimator...

The classical Heckman (1976, 1979) selection correction estimator (heckit) is misspecified and inconsistent if an interaction of the outcome variable and an explanatory variable matters for selection. To address this specification problem, a full information maximum likelihood estimator and a...

We analyse pricing, e¤ort and tipping decisions in the online service GoogleAnswers. While users set a price for the answer to their question ex ante, theycan additionally give a tip to the researcher ex post.In line with the related experimental literature we …nd evidence that tippingis...

We analyse pricing, effort and tipping decisions in the online service "Google Answers". While users set a price for the answer to their question ex ante, they can additionally give a tip to the researcher ex post. In line with the related experimental literature we find evidence that tipping is...

The classical Heckman (1976, 1979) selection correction estimator (heckit) is misspecified and inconsistent if an interaction of the outcome variable and an explanatory variable matters for selection. To address this specification problem, a full information maximum likelihood estimator and a...

A main research focus in many Social Dilemma Games is the suitability of external institutional treatments in inducing socially optimal outcomes. It is likely that participating subjects exhibit unobserved heterogeneity in their reaction to these treatments. This type of “institutional...

We analyse pricing, effort and tipping decisions at the online service ‘Google Answers’. Users set a price for the answer to their question ex ante, and they can additionally tip the researcher who provided the answer ex post.