Domain Testing: Divide and Conquer - Testing Education

1980). But others have described strategies such as boundary value analysis for
selecting best representatives from each equivalence class (Binder, 1999; Hamlet,
2000; Howden, 1980b; Hutcheson, 2003; Jorgensen, 2002; Kaner & Bach, 2003;
Kaner et al., 2002; Kaner et al., 1999; Myers, 1979; White & Cohen, 1980).
In boundary value analysis strategy, test data at the boundaries and just
beyond the boundaries is selected. In addition, some researchers have described
methods such as special value and worst case testing to supplement boundary value
analysis (Jorgensen, 2002). Some have also described proportional partition testing,
a partition testing strategy in which the test data selection is random but the number
of test cases selected from a subdomain depends on the probability of failure of
inputs in the subdomain (Chan, Mak, Chen & Shen, 1997; Chan, Mak, Chen &
Shen, 1998; Chen, Wong & Yu, 1999; Chen & Yu, 1994; Chen & Yu, 1996b; Chen
& Yu, 1996c; Leung & Chen, 2000; Ntafos, 1998; Ntafos, 2001). In other words, if
we were to assume that each input in a subdomain is equally likely to occur, then
the number of test cases selected would depend on the size of the subdomain.
There is also a difference in how linear and non-linear domains and
continuous and discrete domain spaces are analyzed. Some researchers have
described domain testing only for linear continuous space domains (Beizer, 1995;
Clarke, Hassell & Richardson, 1982; White & Cohen, 1980). Others have extended
their description of domain testing methodology to non-linear and discrete domain
spaces as well (Jeng & Weyuker, 1994; Kaner et al., 1999; Zeil et al., 1992b).
While most people in the literature have not described forming equally
sized subdomains, there are some who have suggested partitioning input domain
into equally sized subdomains (Chan et al., 1998; Weyuker & Jeng, 1991).
Finally, there is the difference in the driving force behind testing. Some
researchers have described domain testing strategy as a method of gaining
confidence in the program or for proving the correctness of the program
(Goodenough & Gerhart, 1975; Howden, 1976; Howden, 1979; Howden, 1981;
Howden, 1986; White & Cohen, 1980). Others have described it as a risk-based or
failure-based testing approach (Beizer, 1995; Collard, personal communication,
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