Abstract-This paper analyzes the cost asymmetry through managerial expectations in a nonlinear regression function. Two development determinants, asymmetry co-integration and managerial expectations are also considered. The results revealed that managerial expectation had an impact on the wholesale cost asymmetry response. The managerial optimism is pronounced that show cost asymmetry response for sales, and inventory assets increased higher than decreased with the changing of the expectation basic coefficient and the values of contract parameters. Finally, the impacts of the managerial expectations, cost basic coefficient, and values of the contract parameters are analyzed for illustrating the results of the proposed nonlinear models with the help of numerical experiments. The research examined the short-run and the long-run effects of asymmetry co-integration and managerial expectation changes on the cost behavior in Iraq using the nonlinear regression function.