No. Shariah compliance of Islamic bank does not influence the cost of capital of Islamic banks?

The factors that affect cost of capital are: market opportunities, capital provider's preference, risk, and inflation. "Religiosity" or "religious compliance" (whether shariah or something else) does not have a scientific effect on cost of capital. Moreover, even if some correlation may be observed, such correlation will be a spurious correlation which cannot be relied on, scientifically.

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