Computer-based Laboratory Experiment Research Articles

Using a checklist-based electronic calculation aid and contextual cues to assist medication dose calculation and calculation resumption after interruptions

ObjectivesTo examine whether (1) the use of a checklist-based electronic calculation aid enhanced medication dose calculation and reduced the negative effects of interruptions on calculation, and (2) the use of contextual cues facilitated the resumption of calculation after an interruption. MethodsSixty students in healthcare majors participated in two computer-based laboratory experiments. Experiment 1 examined the effects of the calculation aid and interruptions on calculation error rate, calculation completion time, and perception outcomes. Experiment 2 assessed the effects of contextual cues on resumption error rate, calculation error rate, calculation completion time, and perception outcomes. ResultsIn Experiment 1, calculation error rates were lower for participants who received the calculation aid versus those who did not, and for uninterrupted calculations versus interrupted calculations, although the differences were not statistically significant.The participants spent significantly less time completing the calculation task with the use of the calculation aid than without the use of the calculation aid, and in the case without interruptions than in the case with interruptions. In Experiment 2, the use of contextual cues associated with previous actions significantly reduced the resumption error rate and the completion time of the medication dose calculation. Both experiments showed that the use of the calculation aid and contextual cues was associated with positive attitudes toward the aid and cues, reduced mental effort, and/or higher confidence in task performance. ConclusionsThe use of the checklist-based electronic calculation aid and contextual cues facilitated medication dose calculation and resumption after interruptions and thus has the potential to improve medication safety and work efficiency in healthcare.

Three Barriers to Effective Programs with Payment for Ecosystem Services: Behavioral Responses in a Computer-Based Experiment

Financial incentives in the form of payment for ecosystem services (PES) can encourage participation in voluntary conservation programs, but real-world experience with PES is limited for services such as the provision of endangered species habitats. A computer-based laboratory experiment with 139 US college students as subjects suggests there are three barriers to effective PES programs: (1) financial rewards can crowd out altruism—low-level PES in the experiment was less effective than the same program without PES; (2) landowners may assuage guilt over destroying habitats by making contributions to ineffective conservation programs—participants often paired destruction of habitat with token contributions to conservation efforts; and (3) landowners may strategically exit conservation agreements in ways that are detrimental to wildlife—a large proportion of participants chose to leave agreements and destroy habitats when the PESs were structured without credible deterrence of an early exit. Fortunately, the results of the experiment also suggest research to overcome these barriers by ensuring that PES financial incentives are scaled and structured to effectively promote conservation. The lessons from this study—though they issue from the particular context of this experiment—provide suggestions about how to structure benefit sharing schemes that could be used to promote conservation in a range of settings.

Biomolecules Come Alive: A Computer-Based Laboratory Experiment for Chemistry Students

A series of computer-based laboratory experiments have been developed to aid undergraduate students in appreciating the three-dimensional nature of chemistry and biochemistry. Both lower- and upper-division experiments have been developed. Students are introduced to the use of ChemDraw for the production of professional-quality molecular structures, Chem3D for visualizing molecules in three dimensions, and VMD for investigating protein structures and dynamics. Through a series of guided experiments, students explore important concepts in chemistry and biochemistry, such as stereochemistry, protein secondary structure, intermolecular interactions, molecular recognition, and protein dynamics. An overwhelmingly positive response to these experiments was received, with students reporting an enhanced appreciation of the nature and behavior of molecular and protein systems, and an improved understanding of lecture material.

Time-of-day affects prospective memory differently in younger and older adults

ABSTRACTThe goal of this study was to investigate the impact of circadian arousal on prospective memory performance as a function of age. We tested a younger (18–34 years) and an older group (56–95 years) of participants on- and off-peak with regard to their circadian arousal patterns in a computer-based laboratory experiment. For the prospective memory task, participants had to press a particular key whenever specific target words appeared in an ongoing concreteness-judgment task. The results showed that prospective memory performance was better on- than off-peak in younger but not older participants. Younger participants consistently outperformed older participants in all conditions. We conclude that prospective remembering underlies time-of-day effects which most likely reflect controlled processes.

An experimental investigation into the effects of information revelation in multi-attribute reverse auctions

Bid-takers in multi-attribute reverse auctions (MRA) are typically confronted with a myriad of information revelation options and must make decisions on which pieces of information to reveal to bidders and which ones to conceal. This study explores how the choice of different types and combinations of information can affect bidding behaviour and bidder perceptions in MRA. The results of a computer-based laboratory experiment suggest that by reducing the level of information asymmetry and using certain combinations of information a bid-taker can reduce bidder drop-out and spur the submission of high quality bids, i.e. bids that yield high levels of utility for the bid-taker.

Information revelation in multiattribute English auctions: A laboratory study

The effects of information revelation on allocational and Pareto efficiency are studied in a multiattribute reverse English auction. The setting is a single sourcing problem in which a buyer seeks to acquire an indivisible object from exactly one of five potential suppliers. Bids are three-dimensional with two non-monetary attributes in addition to the object's price. Results from a computer-based laboratory experiment are reported, and observed differences between two information revelation policies are analyzed with respect to the buyer's utility and suppliers' profits. The results suggest that revealing the buyer's preferences increases allocational efficiency. Suppliers successfully use the additional information to make more profits, but not at the expense of the buyer whose utility increases slightly albeit not significantly.

AN EXPLORATORY STUDY OF LIMITED INFORMATION ACQUISITION: DO BRAND NAMES MAKE PRODUCT EVALUATIONS EASY?

Consumers are faced with an enormous amount of information when making product evaluations. Faced with this difficulty, they often try to simplify the evaluation process by limiting their information acquisition. The purpose of this study is to identify two types of such limited information acquisition strategies (IAS), brand-based and attribute-based, and to investigate their characteristics in the product evaluation process. A computer-based laboratory experiment was conducted to gather empirical evidence. The results identified differences in time spent on processing each piece of information, the amount of perceived effort, and the degree of perceived task complexity depending upon which limited IAS consumers utilized. Specifically, the utilization of attribute-based limited IAS simplifies consumers’ information processing, a finding that is consistent with the previous literature. However, that of brand-based limited IAS does not necessarily make the task easy; in fact, it may make it difficult. Implications, limitations and future research directions are discussed.

Food Science Education Publications and Websites

Bird The purpose of this column is to highlight innovative publications and websites in food science education. If you know of a website or a recent publication that you believe other readers would like to know about, please submit the full text of the article or the URL for the website and an annotation of not more than 125 words. We welcome your resources and comments on this column. Material should be submitted to: Jim Bird, Science & Engineering Center, Fogler Library, Univ. of Maine, Orono, ME 04469, or e-mail to Jim.Bird@umit.maine.edu. If e-mailing, please put “JFSE submission” in the subject line. College English (National Council of Teachers of English). 2008. Special topic: Food. 70(4):345–436. This issue of College English is devoted to food writing. Papers include: “Consuming prose: The delectable rhetoric of food writing”, “Food memoirs: What they are, why they are popular, and why they belong in the literature classroom”, and “Books that cook: Teaching food and food literature in the English classroom”. For a very brief description of each article in this special topic issue go to http://www.indiana.edu/~cedialog/?cat=10 Koch P, Barton AC, Contento I, and Crabtree M. 2008. Farm to table and beyond: Helping students make sense of the global food system. Sci Scope 31(9):36–9. The authors describe an activity, part of the Farm to Table & Beyond curriculum, where grade 5 to 6 students diagram the production and processing of food. This activity, utilizing observation and discussion, helps students put the food system into a biological and environmental context. Topics explored in the curriculum include food preservation, environmental effects of food systems, and transportation issues related to food. McDonald J. 2008. Enhancing food-safety education through shared teaching resources. J Vet Med Educ 35(2):207–11. The author describes an innovative project, Design to Dissemination (D2D), developed for veterinary teaching faculty to provide them with food safety resources. The information (called “learning objects”) is presented in various formats including text, animation, audio, powerpoint, and video. The project has three objectives (from p. 208–209): “To provide institutions, faculty, and students with high-quality, clinically relevant, interactive educational materials….; To provide easy access to the materials….; To help faculty use learning objects effectively to build or enhance a course.” A logon is required to fully utilize the site's capabilities but users can create an account. To view this ongoing project, go to the following website: Veterinary Food Safety Education Learning Object Repository http://webcls.utmb.edu/d2d Segner S and Scholthof K-BG. 2007. Environmental microbiology: Bacteria & fungi on the foods we eat. The Am Biol Teach 69(3):149–57. Utilizing fruits and vegetables, a laboratory exercise was developed for the undergraduate course “Pathogens, the Environment, and Society” at Texas A&M Univ. Students concentrated on the identity of cosmopolitan bacteria and fungi on both washed and unwashed fruits and vegetables. Detailed laboratory protocols are presented. The author presents a number of internet resources useful in lab and lecture preparation. Sorgo A, Hajdinjak Z, and Briski D. 2008. The journey of a sandwich: computer-based laboratory experiments about the human digestive system in high school biology teaching. Adv Physiol Educ 32(1):92–9. Based on results from a questionnaire, the authors found that high school students were most successful when hands-on, computer-based experiments were used to teach human digestion. Topics taught included jaw chewing force, dissolution speed, enzymatic breakdown of food, bacteriocidal activity of hydrochloric acid, and importance of the intestine lining's surface. These experiments will be upgraded in the future, based on student input. The authors plan to design experiments to teach other systems. Dairy Science and Food Technology http://www.dairyscience.info (accessed 11/17/2008) This website contains information on the industrial uses of lactic acid bacteria and their bacteriophages, antimicrobial systems in milk, and factors influencing the quality and yield of cheese. There are also sections on starter cultures, probiotics, modeling in food technology, and a summary of information on modified atmosphere packaging. The articles on general food technology include labeling, nutritional claims, wine making and thermal processing. There are calculators and models, such as one for predicting the grade value of Cheddar cheese, theoretical yield of cheese, and a calculator using linear programming for calculating ice cream mixes. The site is aimed at students and practitioners in dairy science and technology, and there are discussion area, extensive links, and literature citations. There are also significant sections aimed at helping students write papers and theses including a Harvard-style reference generator. (Contributed by Dr. Michael Mullan, Head of Higher Education Branch, Greenmount Campus, College of Agriculture, Food and Rural Enterprise, Antrim BT41 4PU, Northern Ireland. michael.mullan@dardni.gov.uk)

The journey of a sandwich: computer-based laboratory experiments about the human digestive system in high school biology teaching

Teaching high school students about the digestive system can be a challenge for a teacher when s/he wants to overcome rote learning of facts without a deeper understanding of the physiological processes inside the alimentary tract. A series of model experiments illustrating the journey of a sandwich was introduced into teaching high school biology. Using a computer equipped with a commercially available data-acquisition system and a couple of sensors, it was possible to illustrate the basic underlying physical and chemical principles of digestion to the students. Students were able to investigate, through hands-on activities, the chewing force of the jaws, importance of the mechanical breakdown of food, enzymatic activity of pepsin and amylase, antibacterial activity of hydrochloric acid, and importance of the villi for absorption. Students found the experiments interesting and helpful for understanding the digestive process. Furthermore, the results from testing indicated that the students had a deeper understanding of the physiological processes.

Determination of absolute zero using a computer-based laboratory

We present a simple computer-based laboratory experiment for evaluating absolute zero indegrees Celsius, which can be performed in college and undergraduate physicalsciences laboratory courses. With a computer, absolute zero apparatus can helpdemonstrators or students to observe the relationship between temperature and pressureand use datalogger software to mathematically extrapolate to find absolute zero.

The accessibility and utility of candidate character in electoral decision making

In U.S. elections, the competence and integrity of candidates for office are among the factors that influence both the choices made by voters and the subsequent outcomes of electoral contests. Although past research has demonstrated that candidate character is highly consequential, much less is known regarding how, and under what conditions, information about character influences the individual-level candidate evaluation. We explore these questions using data from a series of computer-based laboratory experiments and a national survey. Results reveal that attitudes regarding competence and integrity are highly accessible, and that information about competence and integrity strongly influences assessments of candidates. However, no evidence was found that candidate character functions as a default basis of candidate evaluation to be used when information regarding political considerations such as partisanshp and ideology are unavailable.

The interaction of incentives and information disclosure: the case of confidence interval information

Reliable risk assessment is critical for success in decision-making, but our assessment of risk is often hindered by inherent biases and limitations in our information processing capacities. Consequently, many have presumed that the disclosure of probabilistic or confidence interval (CI) information would aid our judgment of the uncertainty of an estimate. Empirical support for CI information disclosure, however, is generally lacking. Since human beings are goal-directed, the effectiveness of CI information disclosure may be contingent upon the motivation of an individual. This study, through a computer-based laboratory experiment, examines whether the effectiveness of CI information disclosure in an investment choice task setting is contingent upon the availability of performance-based monetary incentives. The results indicate that the disclosure of CI information can enhance or harm decision performance contingent upon the incentive condition: incentives are vital for realizing benefits from the disclosure of CI information. The implications of the findings are discussed.

The Impact of Waiting Time Guarantees on Customers' Waiting Experiences

Customers often have to wait during the process of acquiring and consuming many products and services. These waiting experiences are typically negative and have been known to affect customers' overall satisfaction with the product or service. To better manage these waiting experiences, many firms have instituted a variety of programs not only to reduce the actual duration of the wait but also to improve customers' perceptions of it. In this paper, we examine the impact of one such initiative, namely, the institution of a waiting time guarantee, on customers' waiting experiences. A waiting time guarantee is a commitment from a firm to serve its customers within a specified period of time. If the firm fails to meet this commitment for some customers then it compensates them for the delay. Today, a large number of firms in a variety of industries such as fast food, banking, industrial distribution, and healthcare offer such time guarantees to their customers. We develop a utility theory-based model of customers' satisfaction with waiting in line. The model is based upon the assumption that when a customer joins a queue he or she has some prior beliefs about the distribution of service times at the firm. The customer estimates the likely duration of the waiting time on the basis of these beliefs about the service times and the observed queue length. We further assume that as the customer observes the service times for other customers who are ahead in the queue, he or she successively updates these beliefs about the distribution of service times in a Bayesian manner. We then posit that the customer's satisfaction both during as well as the end of the wait is determined by the difference between the customer's updated and the prior estimates of the total waiting time. We apply the model to derive select hypotheses pertaining to the impact of a waiting time guarantee on customers' waiting experiences. These hypotheses are based upon the assumption that an offer of a time guarantee is a signal of reliability from the firm and reduces customers' perceived variance around the expected service times. We empirically test these hypotheses using data from a series of interactive, computer-based laboratory experiments. In these experiments, we used the computer to create animations of reallife waiting experiences. The computer display consisted of a queue of customers waiting for service at a counter. One of the customers represented the participant in the experiment. During the course of the experiment, each participant joined the queue, waited in line for service, and then exited the system. At several points during the wait, each participant reported his or her level of satisfaction with the waiting experience. Our results suggest that if customers observe the service times to be less than expected, their satisfaction increases monotonically during the wait. Further, under such circumstances, the explicit provision of a waiting time guarantee enhances satisfaction both during as well as at the end of the wait. However, if customers observe the service times to be more than expected, then their satisfaction typically declines at the beginning of the wait but increases toward the end of the wait. Further, under these circumstances, the initial positive impact of the provision of a waiting time guarantee declines over time. Moreover, at the end of the wait, customers in guaranteed environments are actually less satisfied than those in unguaranteed environments. Overall, we find that a time guarantee, if met, increases satisfaction at the end of a wait; however, if violated, then it decreases satisfaction at the end of the wait. We discuss the implications of these and other empirical findings for the management of customers' waiting experiences.

Controlling a nonlinear process with variable dead-time: A computer-based laboratory experiment

In process control, nonlinearities and dead-time often play a significant role in the unsuccessful implementation of control systems. This is due to variations in operating conditions and process behaviour affecting controller performance within the stability limitations of the feedback loop. In a laboratory experiment, where a liquid is heated by means of submerged electrical heating elements, temperature control of liquid in a tank by means of a feedback control loop can be investigated. The relationship between the manipulated variable and the tank temperature is non-linear. The loop was designed to contain significant dead-time, dependent on the variable flowrate of liquid through the system. By means of experimentally obtained open loop process reaction curves and by continously measuring the volumetric flowrate, enough information about the process can be obtained to develop a process model compensating for the presence of dead-time and to take the nonlinear behaviour of the process into account. Using a digital measurement and control system, an algorithm was developed which can be used for accurate control of the process. In this paper emphasis is placed on the current ability of computing equipment to apply theoretical concepts which had been known for a long time.