In Tamil Nadu Hosur is a leading area and production of rose flowers in the country (
Mathivanan 2013). Hosur block in Krishnagiri district was purposely selected as the universe of the study, since the area under cut flower crops in this block was found to be the highest with 325.57 hectares among all the blocks present in Krishnagiri district. Hosur block consists of 30 revenue villages. A two-stage random sampling method was adopted to select the sample farms. At the first stage, twelve revenue villages were selected at random. At the second stage, all the farmers in each of the selected revenue villages were arranged and 10 farmers were selected at random from each of the selected twelve revenue villages, thus constituting a total sample size of 120 farmers. The households were post-stratified into three groups based on the income level. Households with annual income of below Rs.25 lakhs were categorized as low-income group, households with annual income between Rs.25 lakhs and Rs.50 lakhs were included under middle income group and those with annual income exceeding Rs.50 lakhs were included under high income group.
Tools of analysis
1. Simple percentage analysis
2. Data envelopment analysis
Data envelopment analysis
The DEA method is a frontier method that does not require specification of a functional or distributional form and can accommodate scale issues. This approach was used by
Forsund (2007) as a piecewise linear convex hull approach to frontier estimation.
Data envelopment analysis
Empirical model
Min θ, λ
θ
Subject to
- y i + Y λ ≥ 0
θ x i - X λ ≥ 0
λ ≥ 0 .....(1)
Where,
yi = A vector (m × 1) of output of the i
th crop producing farms,
xi = Vector (k × 1) of inputs of the i
th crop producing farms,
Y = An output matrix (n × m) for n crop producing farms,
X = The input matrix (n × k) crop producing farms,
q = The efficiency score, a scalar whose value will be the efficiency measure for the i
th crop producing farms. If θ = 1, crop producing farms will be efficient, otherwise, it will be inefficient.
λ = A vector (n × 1) whose values are calculated to obtain the optimum solution.
For an inefficient crop producing farms y values will be weights used in the linear combination of other, efficient crop producing farms, which influenced the projection of the inefficient crop producing farms on calculated the frontier.
The specification of constant returns is only suitable when the firms work at the optimum scale. Otherwise, the measures of technical efficiency can be mistaken for scale efficiency, which considers all the types of returns to production,
i.e., increasing, constant and decreasing. The measure of technical efficiency obtained in the model with variable return is also named as “pure technical efficiency”, as it is free of scale effects.
The following linear programming model estimated is:
Min θ, λ
θ
Subject to
- y i + Y λ ≥ 0
θ x i - X λ ≥ 0
N1 λ = 1
λ ≥ 0 .....(2)
Where,
N1 is a vector (n × 1) of ones.
Tyteca (1996) adapted
Färe et al., (1989) to derive environmental efficiency scores by measuring the degree to which the pollution variable could be reduced given the fixed levels of inputs and desirable outputs. The scale efficiency values for each analyzed unit can be obtained by the ratio between the scores for technical efficiency with constant and variable returns as follows:
θs =
θCRS (XK, YK) /
θVRS (XK, YK) .....(3)
Where,
θCRS (XK, YK) = Technical efficiency for the model with constant returns.
θVRS (XK, YK) = Technical efficiency for the model with variable returns.
θs = Scale efficiency.
It was pointed out that model (2) makes no distinction as to whether crop producing forms is operating in the range of increasing or decreasing returns (2005). The only information one has is that if the value obtained by calculating the scale efficiency in equation (3) is equal to one, the crop producing farms will be operating with constant returns to scale. However, when θs is smaller than one, increasing or decreasing return can occur. Therefore, to understand the nature of scale inefficiency, it is necessary to consider another problem of linear programming,
i.e. the convexity constraint of model (2), N1 l = 1, is replaced by N1 l ≤ 1 for the case of non-increasing returns, or by N1 l ≥ 1 for the model with non-decreasing returns. Therefore, in this work, the following models were also used for measuring the nature of efficiency.
Non-increasing returns:
Min θ, λ
θ
Subject to
- y i + Y λ ≥ 0
θ x i - X λ ≥ 0
N1 λ ≤ 1
l ≥ 0 ......(4)
Non-decreasing returns:
Min θ, λ
θ
Subject to
- y i + Y λ ≥ 0
θ x i - X λ ≥ 0
N1 λ ≥ 1
λ ≥ 0 ......(5)
It is to be stated that all the above model should be solved n times,
i.e. the model is solved for each crop producing farms in the sample.
Production was used as an output (Y) in the present case and seeds/planting materials, farmyard manure (tones/ha), chemical fertilizer (kg/ha), human labour (man days/ha), machine labour (hrs/ha) and plant protection chemicals (lit/ha) as inputs.