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臺大管理論叢
第
27
卷第
3
期
151
As shown in Table 4, Model 3 included interaction among industry age, TMT external
ties, and TMT intra-industry experience addition to test Hypothesis 2, which predicts a
positive moderating effect of TMT external ties on the relationship between intra-industry
experiences and that firm intra-industry performance decreases with industry age. The results
of Model 3 reveal that the coefficient for the three-way interaction is significantly negative
for ties to the CTIA (
γ
= -0.45,
p
< 0.01) and non-significant for ties to other cell-phone
service providers and firms outside the focal industry. In addition, the coefficient for the two-
way interaction between a TMT’s ties to the CTIA and intra-industry experience addition is
significantly positive (
γ
= 4.49,
p
< 0.01), supporting Hypothesis 1 at the emerging stage of
the industry. To check the robustness of the observed effect of industry age in Model 3, we
estimated the specification in Model 2 again by splitting the sample into two groups, one
with an industry age lower than the mean industry age of the full sample and the other with a
higher industry age than that of the full sample. Although not reported here, the results of the
subsample analysis are consistent with the results of Model 3. Thus, Hypothesis 2 is
supported for a TMT’s ties to the CTIA, and Hypothesis 1 is further supported for a TMT’s
ties to CTIA at the emerging stage of the industry of cell-phone services.
In summary, Hypothesis 1 is generally supported but Hypothesis 2 is not for a TMT’s
ties to other cell-phone service providers. Graph 1 shows the marginal benefit of obtaining
one addition tie to the intra-industry competitors. Hypothesis 1 is supported at the emerging
stage of the focal industry for a TMT’s ties to the CTIA. However, this positive moderating
effect of ties to the CTIA gradually decreased with industry age and finally constrained firm
performance, supporting Hypothesis 2. Hypotheses 1 and 2 are not supported for ties to
extra-industry firms. Hence, support for Hypothesis 1 and 2 depends on the type of external
ties that the TMT uses to scan the environment. The results from the fully specified model
are presented in Model 4 in Table 4.