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Alternative-based approaches to decision making generate overall values for each option in a choice set by processing information within options before comparing options to arrive at a decision. By contrast, attribute-based approaches compare attributes (such as monetary cost and time delay to receipt of a reward) across options and use these attribute comparisons to make a decision. Because they compare attributes, they may not use all available information to make a choice, which categorizes many of them as heuristics. Attribute-based models can better predict choice compared to alternative-based models in some situations (e.g., when there are many options in the choice set, when calculating an overall value for an option is too cognitively taxing). Process data comparing alternative-based and attribute-based processing obtained from eye-tracking and mouse-tracking technology support these findings. Data on attribute-based models thus align with the notion of bounded rationality that people make use of heuristics to make good decisions when under time pressure, informational constraints, and computational constraints. Further study of attribute-based models and processing would enhance our understanding of how individuals process information and make decisions. 

The experiment at Jefferson Lab has observed $p\overline{p}$and, for the first time, $\mathrm{\Lambda }\overline{\mathrm{\Lambda }}$and $p\overline{\mathrm{\Lambda }}$photoproduction from a proton target at photon energies up to 11.6 GeV. The angular distributions are forward peaked for all produced pairs, consistent with Regge-like $t$-channel exchange. Asymmetric wide-angle antibaryon distributions show the presence of additional processes. In a phenomenological model, we find consistency with a double- $t$-channel exchange process where antibaryons are created only at the middle vertex. The model matches all observed distributions with a small number of free parameters. In the hyperon channels, we observe a clear distinction between photoproduction of the $\mathrm{\Lambda }\overline{\mathrm{\Lambda }}$and $p\overline{\mathrm{\Lambda }}$systems but general similarity to the $p\overline{p}$system. We report both total cross sections and cross sections differential with respect to momentum transfer and the invariant masses of the created particle pairs. No narrow resonant structures were found in these reaction channels. The suppression of $s\overline{s}$quark pairs relative to $d\overline{d}$quark pairs is similar to what has been seen in other reactions. 

American Physics Society 

The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized 8.5GeV photons impinging on a hydrogen target which is contained within a detector with near-complete coverage for charged and neutral particles. We present measurements of spin-density matrix elements for the photoproduction of the vector meson 𝜌(770). The statistical precision achieved exceeds that of previous experiments for polarized photoproduction in this energy range by orders of magnitude. We confirm a high degree of 𝑠-channel helicity conservation at small squared four-momentum transfer 𝑡 and are able to extract the 𝑡 dependence of natural- and unnatural-parity exchange contributions to the production process in detail. We confirm the dominance of natural-parity exchange over the full 𝑡 range. We also find that helicity amplitudes in which the helicity of the incident photon and the photoproduced 𝜌⁡(770) differ by two units are negligible for −𝑡<0.5GeV2/𝑐2.