Pigeons show a preference for an alternative that provides them with discriminative stimuli (sometimes a stimulus that predicts reinforcement and at other times a stimulus that predicts the absence of reinforcement) over an alternative that provides them with nondiscriminative stimuli, even if the nondiscriminative stimulus alternative is…

Two studies examine how the time at which problem solving is suspended relative to an impasse affects the impact of incidental hints. An impasse is a point in problem solving at which a problem solver is not making progress and does not know how to proceed. In both studies, work on remote associates problems was suspended before an impasse was…

In feeling of knowing (FOK) studies, participants predict subsequent recognition memory performance on items that were initially encoded but that cannot presently be recalled. Research suggests that FOK judgment magnitude may be influenced by the total amount, or quantity, of contextual information retrieved related to the unrecalled target (e.g.,…

In event-based prospective memory, current theories make differing predictions as to whether intention-related material can be spontaneously noticed (i.e., noticed without relying on preparatory attentional processes). In 2 experiments, participants formed an intention that was contextually associated to the final phase of the experiment, and…

Many illustrations and problems on the vector nature of forces have weights and forces in a vertical plane. One of the common devices for studying the vector nature of forces is a horizontal "force table," in which forces are produced by weights hanging vertically and transmitted to cords in a horizontal plane. Because some students have…

Science is a collaborative endeavor. The solitary genius working on the next great scientific breakthrough is a myth not seen much today. Instead, most physicists have worked in a group at one point in their careers, whether as a graduate student, faculty member, staff scientist, or industrial researcher. As an experimental nuclear physicist with…

General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

The antioxidative capacity of phytochemical compounds is often discussed in life science courses (to prevent or slow cancer) and food science courses (to prevent the oxidation of sensitive ingredients). Thus, we developed a laboratory experiment where the photochemical reaction of lightsticks is used to qualitatively demonstrate the antioxidative…

Research designs involving cluster randomization are becoming increasingly important in educational and behavioral research. Many of these designs involve two levels of clustering or nesting (students within classes and classes within schools). Researchers would like to compute effect size indexes based on the standardized mean difference to…

There is much debate over the degree to which language learning is governed by innate language-specific biases, or acquired through cognition-general principles. Here we examine the probabilistic language acquisition hypothesis on three levels: We outline a novel theoretical result showing that it is possible to learn the exact "generative model"…

Once relegated to cinema or history lectures, bank runs have become a modern phenomenon that captures the interest of students. In this article, the authors explain a simple classroom experiment based on the Diamond-Dybvig model (1983) to demonstrate how a bank run--a seemingly irrational event--can occur rationally. They then present possible…

Synthesis of 4-methylumbelliferone via the acid-catalyzed Pechmann condensation introduces students to several types of organic reactions: transesterification, electrophilic aromatic substitution, and alcohol dehydration. Performed with a recyclable, solid catalyst and under solvent-free conditions, the experiment illustrates many of the…

Chemoselectivity is a central concept in organic synthesis and may be readily appreciated in the context of the fragrant, polyfunctional natural product citral. We describe three single-step reactions students may perform on citral to synthesize other natural perfumes: citronellal, geraniol, nerol, or epoxycitral. Each of the reactions uses a…

The cross modal repetition priming paradigm was used to investigate how potential lexically ambiguous no-release variants are processed. In particular we focus on segmental regularities that affect the variant's frequency of occurrence (voicing of the critical segment) and phonological context in which the variant occurs (status of the following…

The question whether to walk slowly or to run when it starts raining in order to stay as dry as possible has been considered for many years--and with different results, depending on the assumptions made and the mathematical descriptions for the situation. Because of the practical meaning for real life and the inconsistent results depending on the…