The Online Laboratory: Conducting Experiments in a Real Labor Market

Online labor markets have great potential as platforms for conducting experiments, as they provide immediate access to a large and diverse subject pool and allow researchers to conduct randomized controlled trials. We argue that online experiments can be just as valid---both internally and externally---as laboratory and field experiments, while requiring far less money and time to design and to conduct. In this paper, we first describe the benefits of conducting experiments in online labor markets; we then use one such market to replicate three classic experiments and confirm their results. We confirm that subjects (1) reverse decisions in response to how a decision-problem is framed, (2) have pro-social preferences (value payoffs to others positively), and (3) respond to priming by altering their choices. We also conduct a labor supply field experiment in which we confirm that workers have upward sloping labor supply curves. In addition to reporting these results, we discuss the unique threats to validity in an online setting and propose methods for coping with these threats. We also discuss the external validity of results from online domains and explain why online results can have external validity equal to or even better than that of traditional methods, depending on the research question. We conclude with our views on the potential role that online experiments can play within the social sciences, and then recommend software development priorities and best practices

Iceland: history and politics

yesThe full text of the author's final draft was made available May 2016, at the end of the publisher's embargo

Iceland: History

ye

Yugoslavia

It remains one of the saddest ironies in the history of conflict in the twentieth century that Yugoslavia, of all those communist states of Eastern Europe which transformed in its penultimate decade, was the one that had demonstrated the greatest degree of liberalization in its social, political, and economic structure and development, yet was the one that disintegrated amid the greatest violence and loss of life

Synergies between processing and memory in children's reading span.

Previous research has established the relevance of working memory for cognitive development. Yet the factors responsible for shaping performance in the complex span tasks used to assess working memory capacity are not fully understood. We report a study of reading span in 7- to 11-year old children that addresses several contemporary theoretical issues. We demonstrate that both the timing and the accuracy of recall are affected by the presence or absence of a semantic connection between the processing requirement and the memoranda. Evidence that there can be synergies between processing and memory argues against the view that complex span simply measures the competition between these activities. We also demonstrate a consistent relationship between the rate of completing processing operations (sentence reading) and recall accuracy. At the same time, the shape and strength of this function varies with the task configuration. Taken together, these results demonstrate the potential for reconstructive influences to shape working memory performance among children

Are Online Labor Markets Spot Markets for Tasks?: A Field Experiment on the Behavioral Response to Wage Cuts

In some online labor markets, workers are paid by the task, choose what tasks to work on, and have little or no interaction with their (usually anonymous) buyer/employer. These markets look like true spot markets for tasks rather than markets for employment. Despite appearances, we find via a field experiment that workers act more like parties to an employment contract: workers quickly form wage reference points and react negatively to proposed wage cuts by quitting. However, they can be mollified with “reasonable” justifications for why wages are being cut, highlighting the importance of fairness considerations in their decision making. We find some evidence that “unreasonable” justifications for wage cuts reduce subsequent work quality. We also find that not explicitly presenting the worker with a decision about continuing to work eliminates “quits,” with no apparent reduction in work quality. One interpretation for this finding is that workers have a strong expectation that they are party to a quasi-employment relationship where terms are not changed, and the default behavior is to continue working

Are Online Labor Markets Spot Markets for Tasks?: A Field Experiment on the Behavioral Response to Wage Cuts

In some online labor markets, workers are paid by the task, choose what tasks to work on, and have little or no interaction with their (usually anonymous) buyer/employer. These markets look like true spot markets for tasks rather than markets for employment. Despite appearances, we find via a field experiment that workers act more like parties to an employment contract: workers quickly form wage reference points and react negatively to proposed wage cuts by quitting. However, they can be mollified with “reasonable” justifications for why wages are being cut, highlighting the importance of fairness considerations in their decision making. We find some evidence that “unreasonable” justifications for wage cuts reduce subsequent work quality. We also find that not explicitly presenting the worker with a decision about continuing to work eliminates “quits,” with no apparent reduction in work quality. One interpretation for this finding is that workers have a strong expectation that they are party to a quasi-employment relationship where terms are not changed, and the default behavior is to continue working

Are Online Labor Markets Spot Markets for Tasks?: A Field Experiment on the Behavioral Response to Wage Cuts

In some online labor markets, workers are paid by the task, choose what tasks to work on, and have little or no interaction with their (usually anonymous) buyer/employer. These markets look like true spot markets for tasks rather than markets for employment. Despite appearances, we find via a field experiment that workers act more like parties to an employment contract: workers quickly form wage reference points and react negatively to proposed wage cuts by quitting. However, they can be mollified with “reasonable” justifications for why wages are being cut, highlighting the importance of fairness considerations in their decision making. We find some evidence that “unreasonable” justifications for wage cuts reduce subsequent work quality. We also find that not explicitly presenting the worker with a decision about continuing to work eliminates “quits,” with no apparent reduction in work quality. One interpretation for this finding is that workers have a strong expectation that they are party to a quasi-employment relationship where terms are not changed, and the default behavior is to continue working

With development, list recall includes more chunks, not just larger ones.

The nature of the childhood development of immediate recall has been difficult to determine. There could be a developmental increase in either the number of chunks held in working memory or the use of grouping to make the most of a constant capacity. In 3 experiments with children in the early elementary school years and adults, we show that improvements in the immediate recall of word and picture lists come partly from increases in the number of chunks of items retained in memory. This finding was based on a distinction between access to a studied group of items (i.e., recall of at least 1 item from the group) and completion of the accessed group (i.e., the proportion of the items recalled from the group). Access rates increased with age, even with statistical controls for completion rates, implicating development of capacity in chunks. (PsycINFO Database Record (c) 2010 APA, all rights reserved