Editorial: The journal impact factor

This issue contains three divergent papers. The first, Modular formal verification of specifications of concurrent systems, by Gradara, Santone, Vaglini, and Villani, proposes a bottom-up approach to verifying modular systems. Properties of components are first verified, then emergent properties of the system as a whole are verified. The approach is applied to a web service. The second paper, Simulated time for host-based testing with TTCN-3, by Blom, Deiss, Kontio, Rennoch, and Sidorova, describes a method to test real-time embedded software. When real-time software is tested in a development environment where the timing characteristics do not match the target environment, this research proposes using simulated time to test the real-time properties. The third paper, IPOG/IPOG-D: Efficient test generation for multi-way combinatorial testing, by Lei, Kacker, Kuhn, Okun, and Lawrence, presents two new strategies for t-way combinatorial testing. The strategies have been implemented in a tool, FireEye, which is available on the first author’s website. Software engineering researchers have always developed tools, but most tools have not easily been available to other researchers. This positive trend has the ability to multiply the impact of our research, which brings me to the main subject of this editorial. Many readers of Software Testing, Verification and Reliability may not be familiar with the ‘impact factor,’ but it is the major way that journals currently are evaluated. It is used almost exclusively worldwide by publishers, universities, research organizations, and government agencies to judge the impact of scientific journals. The factor is used to make hiring decisions, determine promotion and tenure, allocate research funding, and determine whether PhD students should be allowed to graduate. I first heard of this measurement when a visitor told me that she could not graduate without a journal paper, and the list of acceptable journals was determined solely by this specific measure. Thomson Scientific’s Journal Citation Reports is the recognized authority for evaluating journals [1]. It publishes statistics that are intended to objectively evaluate scientific journals and how they influence the global community of researchers. The statistics they compute are broad and multifaceted. Unfortunately, the research community seems to have narrowed down to one specific measure, the impact factor, to measure journals. The primary advantage of the impact factor is that it is very easy to measure. Unfortunately, it does not capture the true quality of research papers, their effectiveness, or the long-term impact of journals. Journal Citation Reports defines the impact factor as the frequency with which the ‘average article’ in a journal has been cited in a particular year [2]. It is calculated on a year-by-year basis. For year Y , the number of citations to papers published in the journal during years Y -1 and Y -2 is