The molecular mechanisms that govern bone and joint formation are complex, involving an integrated network of signaling pathways and gene regulators. We investigated the role of Hox genes, which are known to specify individual segments of the skeleton, in the formation of autopod limb bones (i.e., the hands and feet) using the mouse mutant synpolydactyly homolog (spdh), which encodes a polyalan...

The share of household resources devoted to children is hard to identify, because consumption is measured at the household level, and goods can be shared. Using semiparametric restrictions on individual preferences within a collective model, we identify how total household resources are divided up among household members, by observing how each family member's expenditures on a single private go...

The existing superstar model (Rosen 1981) does not require imperfect substitutes and explains the convexity of total earnings with respect to talent due to higher output for those with the most talent. We develop a model that explains why per unit earnings (wages or prices) would increase at an increasing rate in talent. Imperfect substitution results due to the probabilistic nature of producti...

Economists typically object to preference-based explanations of human behavior; differences in preferences “explain everything and therefore nothing”. But this argument is only correct assuming that no empirical evidence exists to discipline preference-based explanations. In fact, over the past decade, personality psychologists have produced a robust collection of stylized facts about human pre...

Advertising messages compete for scarce attention. “Junk” mail, “spam” e-mail, and telemarketing calls need both parties to exert effort to generate transactions. Message recipients supply attention depending on average message beneÞt. Senders are motivated by proÞts. Costlier message transmission may improve message quality so more messages are examined. Too many messages may be sent, or the w...

We study noncooperative household models with two agents and several voluntarily contributed public goods, deriving the counterpart to the Slutsky matrix and demonstrating the nature of the deviation of its properties from those of a true Slutsky matrix in the unitary model. We provide results characterising both cases in which there are and are not jointly contributed public goods. Demand prop...

Let X be a compact, or path-connected, metric space whose topological dimension is at least 2. We show that there does not exist a continuous choice function (i.e., single-valued choice correspondence) defined on the collection of all finite feasible sets in X. Not to be void of content, therefore, a revealed preference theory in the context of most infinite consumption spaces must either relin...

If preferences or budgets are heterogeneous across people (as they clearly are), then individual costof-living indices are also heterogeneous. Thus, any social cost-of-living index faces an aggregation problem. In this paper, we provide a solution to this problem which we call a ’common-scaling’social cost-of-living index (CS-SCOLI). In addition, we describe nonparametric methods for estimating...

In the measurement of inequality, adjustments for differences across households in their demographic composition and in the price regimes they face are usually very simple. Often, nominal expenditure (or income) is adjusted with an expenditure-independent price deflator and a price-independent equivalence scale. I show that using more flexible expendituredependent price deflators and price-depe...