A set of well known necessary conditions for the existence of a large set of t-designs, LS[N ](t, k, v), is N ∣∣∣(v−i k−i) for i = 0, . . . , t. We investigate the existence of large sets of size four. We take advantages of the recursive and direct constructions to show that the trivial necessary conditions are sufficient when N = 4, t = 2, 3 and k ≤ 7.

Virtual teams play an increasingly important role in the modern economy, and many organizations struggle to overcome the weaknesses inherent in technology-mediated work. Identity communication has been shown to greatly improve individualand group-level outcomes in offline settings, but these benefits have not been investigated in the context of virtual teams, where mediated interaction can affe...

This experiment sought to examine the equivalence of online and paper and pencil testing methods as related to student performance in a computer technology course. Test score and completion time were the dependent variables that were used to assess students’ performance. The study utilized a quasi-experimental design. Test scores were not significantly different on the variables of pretest, age...

Let D be a statistical design consisting of v varieties on b blocks. We say it is binary if a variety occurs at most once on every block. For varieties p and q on blocks x and y respectively, we can obtain design D' from D by interchanging p and q (so p is on y and q is on x). We say that the exchange is binary if either x y, or p q, or: q not on x and p not on y. If D is binary then D' is also...

A project suitable for use as a first and last assignment given in an introductory experimental design course is outlined, and its implementation discussed. Phase 1 of the project is designed to be given at the beginning of a first course in experimental design and involves designing an experiment within instructor-specified parameters based initially on intuition and common sense. Phase 2, at ...

Experimental auctions are generally thought of as static markets. This paper presents the results of an experimental auction designed to test whether participants’ perceptions regarding the relative difficulty of delaying or reversing a transaction outside the experimental market systematically affect their willingness-to-pay bids. The results show that auction participants’ perceptions signifi...

This paper describes a new methodology for the speech quality assessment of hands-free terminals and discusses the results of a pilot study performed in 1996 at the Berlin laboratories for speech quality assessment at the Technology Centre of Deutsche Telekom. Up to now, critical speech quality aspects of hands-free terminals are usually assessed with conversational tests. With the test method ...

While IT is generally found to augment productivity, recent evidence indicates that excessive and compulsive usage of IT is likely to have some adverse consequences. Given the prevalence of IT addiction, it becomes increasingly important to study this phenomenon. We seek to investigate the adverse effects of IT addiction, especially on productivity, in work settings. We propose a model showing ...