Model and Methodology
At this section, w investigate research question by using a questionnaire to collect data. After
collecting, I use SPSS software to control relation between our variables by regression analysis.
Model have three phases. In first phase, five dimensions are used of all GSCM dimensions
which affect fuel consumption & maintenance, repairing expenditure. In second phase, the well
known relation with fuel consumption & maintenance, repairing expenditure (FCMRE) and
transportation cost reduction is used to get result for this study. Transportation cost reduction side is
third phase in our model. One point about methodology should be clarified in second phase (see Model
1).
The reverse relation between fuel consumption & maintenance, repairing expenditure and
transportation cost reduction. But the diffuculties of finding fluctuation in transporation cost reduction
in a direct way. To get result about transportation cost reduction, I use the second phase as a step
phase. Through second phase, I get effect of five dimensions into fuel consumption & maintenance,
repairing expenditure, then using result and using reverse relation, I reach the point which explains the
effect of five dimensions into transportation cost reduction.