The study was mainly based on primary data that were collected through face to face interview using a pre-tested interview schedule which was conducted through field survey during the month of December, 2016 to March, 2017. Rajshahi and Joypurhat district was the pioneer of strawberry cultivation. At present strawberry is being cultivated by the farmers of Tangail, Kumilla, Sathkhira, Khagrachari and Coxbazar in scattered way but in Rajshahi and Joypurhat a good number of farmers are cultivating strawberry. So, Rajshahi and Joypurhat were selected for this study. Sampling technique and sample size: Multistage sampling technique was followed to collect sample farmers for this study. At first, two districts namely Joypurhat and Rajshahi were selected on the basis of availability of strawberry farmer. In the second stage, concentrate strawberry growing upazila from each district were selected on the basis of area and production of strawberry. Sadreupazila from Joypurhat and Charghatupazila from Rajshahi were sele cted. Thirdly, 2-3 agricultural Blocks were selected in consultation with DAE personnel for selecting sample farmers. Finally, the samples were randomly selected from the complete list of strawberry farmers for interview. Mari (2009) and Ali et al, (2017) stated that 60 sample was appropriate for decision making in case of large population. However, a total of 100 strawberry growers taking 50 farmers from each district were selected for the study. Open source software R, Microsoft Excel and STATA-10 were used for analyzing results. Production function and its stages: Production function is a functional relationship between output and inputs (Jhingan, 2007). There are three stages of production. MPP is negative in stage III and it is not rational to produce with negative MPP (Akighir and Shabu, 2011).
Model Specification: The Cobb-Douglas production model was useful for the estimation of resource use efficiency due to econometric and statistical advantages like sign and size of coefficients, t-test, f-test and R 2 (Ashfaq et al., 2012).It was also used in many studies (Abid et al., 2011; Ali et al., 2017; Khatun et al., 2017; Ibitoye et al., 2015; Umar and Abdulkadir, 2015). The double-log function (Cobb-Douglas) provided the best fit and was therefore chosen for the study (Olomla, 1991; Mbata et al., 1993). Using the ordinary least square (OLS) estimator, the production response function model was expressed implicitly as: Y = f (X 1, X 2, X 3, X 4, X5, X6, X7, Ui) ................ (1) Where Y = quantity of output in kilograms, X 1= labour(man-days), X 2 = no. of sapling, X 3 = quantity of cowdung in kilograms, X 4 = quantity of fertilizer in kilograms, X5=land (farm size), X6= quantity of water in liter and X7= quantity of chemicals in kilograms. The functional form of the double-log function was ex-pressed as follows: lnY = b0 + b1lnX1+b2lnX2+ ......... + b7lnX7 + e ......... .. (2). Resource use Efficiency: It is a ratio between Marginal Value Product (MVP) for a specific input and Marginal Factor Cost (MFC) of that particular input (Abid et al. 2011; Ashfaq et al. 2012; Mohammed et al. 2014; Umar and Abdulkadir, 2015; Ali et al. 2017) as: ri=MVPi / MFCi………..(3) where: ri = Resource use efficiency ratio MVPi = Value of additional output by using an additional unit of a particular input resource MVPi = MPPi x Py ................. (4). MFCi = PXi = It is price of one unit of input resource. Where, Py and MFCi, are the unit prices of output and factor input respectively. The marginal physical product (MPP) was given by: MPPi = bi x APPi .................(5), Where bi = elasticity’s of the various inputs.