In this paper, we discuss several concepts in causal inference in terms of causal diagrams proposed by Pearl (1993, 1995a, b), and we give conditions for non-confounding, homogeneity and collapsibility for causal e€ects without knowledge of a completely constructed causal diagram. We ®rst introduce the concepts of non-confounding, conditional non-confounding, uniform non-confounding, homogeneit...

New statistical methods allow discovery of causal models from observational data in some circumstances. These models permit both probabilistic inference and causal inference for models of reasonable size. Many domains, such as education, can benefit from such methods. Educational research does not easily lend itself to experimental investigation. Research in laboratories is artificial and poten...

A rcccnt trend in cxpcrt systems rcscarch has been toward systems which reason from descriptions of causnl processes in the domain, rather than from the surface cffccts. ‘I’his is the “causal model” versus “cinpirical association” distinction prcscntcd in [2]. Typically, this involves creating a dctailcd model of the physical proccsscs which undcrly the domain. ‘I’his model must support infcrcn...

Telemedicine, enabled by state-of-art information technology, is rapidly gaining awareness in many countries. Despite the advanced telecommunication infrastructure, the introduction of telemedicine in Hong Kong has been slow. Hong Kong’s monopolistic health care system provides an answer for the protracted development of telemedicine in the region. This study attempts to reach a theoretical und...

Commercially successful video games easily sell more than one million units in the US market alone and gross more than $ 100 million. Few research approaches have asked the question what makes a video game succeed in the market. This paper focuses on the role of external information sources. As video games are experience goods whose value for the consumer only becomes apparent after he or she h...