The primary methodological challenges of empirical work on why
livestock production is scaling up are to define a quantitative measure of
relative farm competitiveness in production and then to look in a structured
way at all the factors that differ across farms that might explain higher relative
competitiveness among farms. The latter include technical and allocative
efficiency, asymmetries in access to assets (credit, liquidity, fixed capital,
etc.) and information (education, experience, etc.), externalities (some
farmers get away with uncompensated pollution while others do not), and
policies (some get a better deal from the state than others).
The omission of relevant factors-such as considering differential
efficiency across farms in explaining competitiveness while neglecting transaction
cost differences, or vice versa-leads to biased estimates. Furthermore,
inclusion of explanatory factors of relative competitiveness that are
themselves functions of relative competitiveness leads to simultaneity bias.
For example, relative competitiveness might be enhanced through being
recognized as a sales leader, but being recognized as a sales leader may depend
on being more competitive than others. The two-way causality among the
variables leads to bias in the empirical estimation of the effect of all
variables unless appropriate procedures are used.
3.1 Defining a Farm-Specific Measure of Relative Competitiveness
Relative competitiveness might be thought of as the ability to
produce at a lower unit cost of production than one's competitors. In fact, if
large farms can produce livestock at a lower unit cost than small ones, they
will clearly drive small farms out of the market over time. The market price
that applies to both large and small, by this reasoning, will fall as
large-scale producers expand production, and the small farms will get squeezed
out. The only future for smallholders then will be to stay in a few
higher-priced niche markets that are not economic for larger farms to serve and
to cut costs by paying their own (family) labor less than a large farmer pays
hired labor. Even so, it is unlikely that smaller producers will be able to
stay in business long under this situation.
However, the reverse is not necessarily true: if small farms can
produce at lower unit costs than large farms, they may still be squeezed out.
This is because large-scale farms can remain profitable with very thin profit
margins; they make up in volume what they lose in per unit profit. Very low per
unit profits coupled with a small sales volume may not provide enough income
for a smallholder to stay in business. Thus, if large farms have lower per unit
costs of production when all labor is costed at market wages, the next question
is whether this finding still holds if smallholders do not cost their family
labor. If it does, then it is not necessary to proceed further; there is little
hope for smallholders in this activity.
If, on the other hand, small farms can produce at a lower per unit
cost in the same markets as large farms, perhaps by not costing their own labor
at full market wage rates or by some other means, there is at least hope for
them. Thus, having higher unit profit, with or without the cost of family
labor, is a necessary condition for the competitiveness of smallholders, but
not a sufficient one.
For a more satisfactory measure of relative competitiveness-one
that gets around the issue of larger farms being able to expand production
while small ones cannot-it is necessary to appeal to the notion of efficiency.
Small farmers are most likely to be able to stay in business-and perhaps to
gain market share-if they are more efficient users of farm resources, both in a
technical sense (being on the production possibility frontier, given existing
technology) and the allocative sense (being at the right place on the
production frontier, given prevailing prices). If small farms are more
efficient users of farm resources, perhaps because they put more care per unit
of input into what they do, then they have a market advantage over large-scale
producers that will be difficult to overcome. This then yields a measurable
index of relative competitiveness: relative farm efficiency in securing profit
per unit of output. Ceteris
paribus, farmers who are more efficient users of farm resources to secure
profits per unit of output are more likely to be able to maintain market share
than larger producers who are less efficient in the same sense. Over time, the
more efficient are in a position to invest more in the farm enterprise and to
grow, whatever their starting size.
A standard way of assessing farm-specific relative profit
efficiency is to estimate a "profit frontier" across a sample of
farms and then to measure how far each farm in the sample lies below the
frontier. Conceptually, such a frontier can be thought of as a function of
mapping profit per unit to relative input and output prices and quantities of
nontraded factors of production, where each point is the maximum profit per
unit that a farm can achieve given those relative prices and access to
resources. Given a set of prices, the average farm with that level of resources
will fall below the frontier. Thus, an ordinary least squares (OLS) regression
on data from a sample of farms of different sizes of profit per unit of output
against input and output prices and fixed factors of production (land, labor,
etc.) will always lie below the theoretical frontier. The frontier itself has
to be estimated in some fashion by looking at data for farms that perform best
at each level of resources. Fried, Lovell, and Schmidt (1993) describe various
approaches to this problem.
The measurement of "most efficient" can be improved by
estimating a stochastic profit frontier, which allows for
measurement error in the econometric estimation of the frontier itself and thus
for the fact that observations for some farms will lie above the estimated
"best" frontier (see Battese 1992 for a survey of this literature).
In our case, the dependent variable is profit per unit of output, and the
explanatory variables are farm-specific fixed resources (land, family labor,
sunk capital); farm-specific input prices (feed, medicines, stock, etc.); and
farm-specific output prices. In this country's situation, farm resources such
as land may be non-tradable inputs and must be accounted for in the frontier in
terms of the amount available, not their price. The unit prices received for
output and prices paid for inputs can also be expected to vary greatly and to
reflect (and control for) quality differences and differential transaction
costs such as bargaining power and riskiness.
Farm-specific profit efficiency (deviations below the frontier)
are measured as the ratio of actual profit per unit (Yi in Figure 3.1 for a farm i) and ideal profit (Y*). Note
that the curve denoting average profit for any given level of resources (shown
as the locus of points Y in Figure 3.1)-estimated by OLS regression --is less
than ideal profit. The measure of farm efficiency embodied in Yi/Y*
is bounded by 1 (best-on the frontier) and worst (0, no profit). Farm-specific
inefficiency is the distance below the frontier, (Y* minus Yi).
If small farms have on average significantly higher profit
efficiency per unit of output when family labor is not costed, then there is
hope. This is even more true if it holds when family labor is costed at market
wage rate. However, this methodology allows going beyond simply making this
determination; it also permits the investigation into which elements contribute
most to explaining relative unit profit efficiency for large and small farms.
Individual farms, large or small, may lie well below the profit frontier for
reasons other than technical or allocative inefficiency: farm-specific
transaction cost barriers or policy distortions may also affect their position
relative to the frontier.
3.2 A Methodology to Decompose the Determinants of Relative
Profitability
The
stochastic profit frontier used in this study to estimate profit efficiency is
defined asYi = f (Xi,Wi, Pi;b)exp(vi -ui) (1)
where Yi = profit per farm i normalized by quantity of output Qi (i.e., unit profit) defined as:
Yi =((PiQi - CiQi)/Qi) (2)
where:
PiQi = total revenue from dairy activity per farm i in question (manure sales included);
CiQi = total variable costs, such as costs of
feed, fodder, hired labor, veterinary services, medicines, breeding, extension
services, transport, maintenance of building and equipment, and other overhead,
and of securing revenue, excluding family labor per farm i; and Qi = quantity of milk (in liters)
produced per farm i;
Xi= vector of
fixed factors used to obtain Yi (e.g., stock of family labor,
land, buildings and equipment, and fixed capital stock, to control for
differences in farm resources) normalized by Qi;Wi= vector of farm-specific input prices;
Pi= weighted average price of milk (weights are the farm-specific transaction quantities);
b= vector of unknown parameters to be estimated; and
vi, ui are random error terms.
3.2.2 Second Stage: Technical Inefficiency Determinant Model
Battese
and Coelli (1995) base their approach on the assumption that the expected value
of the farm-specific inefficiency effect for farm i can be modeled as a function of
farm-specific characteristics, which of course vary across farms, and fixed
coefficients, which do not. In other words,
where µi = zik dk is the mean of a truncated-normal
distribution of ui.
The zik are k explanatory variables observed for
farm i, associated with
technical inefficiency effects (ui), and d is a vector of unknown
coefficients to be estimated simultaneously with equation (1). Thus, the
technical inefficiency effect ui in equation (1) can then be specified
as ui = zik dk + ei, where ei is the inefficiency error term,
defined by the truncation of the normal distribution with mean equal to zero
and variance s2. The truncation of ei occurs at ei ³ -zikdk (Battese and Coelli, 1995).[68]
A
translog profit frontier is used because of the flexibility it allows in
estimating parameters where it is not desirable to build in through model
specification rigid assumptions about substitution relationships among inputs
and factors. The full form of the model is:
where Yi is the normalized profit of the i-th farm defined in equation
(2); Wij is the price of input j (j = hired labor, feed concentrate,
and dry and green fodder used by the i-th
farm); Xik is the fixed factor k used by the i-th farm (k = the normalized value of buildings
and equipment, normalized total farm labor in minutes, and land in hectares).
The vi, ui are as previously defined. The akj, jkk, bjk are coefficients to be estimated by
MLE using Frontier 4.1 software (Coelli, 1992).
Normalizing by output quantity builds in an assumption of constant
returns to scale, so to allow for the fact that larger producers may in fact be
using higher grade technology than others, we need to control for non-Hicks
neutral technical change on the RHS (right hand side) of the first stage of our
stochastic profit functions. To deal with this problem, we allow for the
parameterization of Hicks non-neutral technological change by including the
"yield" variable, which is probably closely correlated with both technology
and managerial ability, calculated as total liters of milk per farm divided by
total number of milk animals for that farm. The resulting weighted-average milk
output per animal is a good proxy variable for technological progress.
Translog profit frontiers share the use of logarithms in the
dependent variables and thus do not handle cases of negative or zero unit
profits. Yet it is not unreasonable to suppose that farms lose money in some
years. There is in fact no perfect fix for this problem, and we employ a
lesser-of-the-evils approach that is adequate for present purposes. A constant
scalar is added to the unit profit data in each sample so that the unit profit
of every farm is positive. As long as the cases of negative average farm
profits are few (less than 5%, say) and they are proportionately not very
negative relative to average farm unit profit (so that the scalar is small
relative to the mean), the resulting bias from a nonlinear transformation of
the data is judged to be of minor importance compared to the bias that would
arise from using a less appropriate functional form or arbitrarily dropping the
least efficient sample members.
The technical inefficiency effects (ui s) generated in equation (3) are estimated within the MLE model specified above as:
ui = d0 + d1Z1 + d2Z2 ... + ei (4)
where Zi is the i-th farm characteristic determining relative inefficiency and ei is distributed as above.
The RHS variables of equation (4)-that is, the Z-cover all the farm
characteristics that proxy different levels of transaction costs faced by each
farm, such as access to credit for capital, access to information, age of
decision maker, education of decision maker, distance to market, membership of
decision maker in an organization, zone dummy as proxy for policy distortion,
and environmental cost.
Two
remaining methodological problems concern the measurement of the farm-specific
data. First, some of the explanatory variables that we may wish to include in
the second stage may not be observable at all or may be very hard to observe.
This is especially true of transaction cost and externality variables. Second,
some of the explanatory variables that we may wish to include in the second
stage may be endogenous in the sense discussed above: the causality goes both
ways, introducing simultaneity bias in estimation. This is particularly a
problem for environmental externalities, since farm-specific differences here
will help to determine relative unit profit efficiency as we define it, but
themselves may be a function of the latter in some cases.
3.3 Measuring Farm-Specific Internalization of
Environmental Externalities
Two problems arise in trying to account for the fact that some
farms pollute more per unit of output than others in assessing why some farms
have higher profits than others. The environmental externalities of livestock
production are both hard to measure and, in many cases, determined
simultaneously with the level of actual profit per unit. An externality is
defined here as a return to an economic agent where part of the cost (or
benefit) of undertaking an activity accrues to another entity that is not
compensated (or charged) in the market. Negative externalities may be created
in the production process for animal agriculture through odor, flies, and the
nutrient-loading effects on soil of manure that is either mishandled or
supplied in excess. Producers capture the benefit of negative externalities by
receiving payment for livestock output while not bearing the full costs to all
of their enterprise in terms of the impact on surrounding communities of odor,
flies, poor water quality, and so forth. Producers who do not pay the full cost
of production per unit may show up as more efficient (in financial terms) than
producers who are otherwise similar but internalize some of the externality by
cleaning up after the enterprise or by making compensatory payments to
surrounding communities.
The first problem is how to measure the value of not paying for
pollution created, particularly if this differs by scale of farm, since it will
lead to erroneous comparisons of unit profits across scale categories. Such
externalities are exceedingly difficult to measure. There is the issue that
farmers themselves suffer some of their own pollution, and this needs to be netted
out of the externality. There is the issue that the negative effects of
pollution carry over into the future. Physical measurements of costs in terms
of decreased sustainability are also very difficult. Furthermore, the true
consequences for sustainability of a given amount of manure will differ by soil
type, temperature, rainfall, and so forth.
In view of these difficulties, it is not practical in the present
study to attempt to measure actual negative externalities. Instead, we focus on
differences across farms in the amount of externality "internalized"
when a farmer invests in pollution abatement, through handling manure and dead
stock in an ecologically sound manner. Higher expenditure per unit of output on
a given farm for abatement of environmental externalities, other things equal,
should be inversely correlated with the incursion of net negative environmental
externalities per unit of output under the assumptions above. Thus, a farm that
spends more per unit of output on environmental abatement is postulated to
incur fewer negative environmental externalities than a farm that spends less
on environmental services per unit of output.
The heroic assumption that allows us to proxy environmental
mitigation with the money value of manure management is that a given amount of
manure of a given sort is equally polluting, whatever farm it comes from, if it
is not spread on fields (one's own or someone else's). This assumes that
spreading manure on crops is uniformly good (despite runoff into watercourses in
some cases) and ignores the fact that farms close to population centers and
watercourses probably produce more ecological harm per ton of manure than those
far from people and watercourses, other things equal. By the same logic, if we
are willing to assume that the relationship is cardinal as well as ordinal-$1
per 100 kg of output in abatement on farm A is twice as environmentally
friendly as $0.50 per 100 kg of output on Farm B-we have a workable index that
differentiates (inversely) across farms in the amount of negative environmental
externalities incurred. The assumptions are not perfect, but the only feasible
alternative-of ignoring negative externalities altogether in econometric
production work-seems worse.
The components that go into a measure of environmental mitigation
include imputed value of manure, annualized expenditures on manure storage
sheds, transportation cost of manure from farm to end-use point, cost of
spreading manure in the field, cost of making dung cakes (if used as fuel),
expenditure per unit of milk, taxes, and other costs of compliance in dealing
with environmental problems. In addition, the spreading of manure on crops is
considered to transform a potential externality (pollution) into a positive
contribution to soil structure and fertility. This benefit is hard to cost with
accuracy. The simple approach adopted is to value all manure sold for spreading
on the fields of others (the reason it is purchased) at its sale value at the
producing farm gate. Manure spread on one's own fields is valued at what it
could have been sold for at the farm gate. Thus, if manure is spread on the
field and has any market value (i.e., people are not just dumping), the latter
is included in the internalization of the externality. The worst that any farm
can do under this approach is to have no abatement expenditure at all per unit
of output, and this is, in fact, the case for many farms.
Having a working index of environmental mitigation creates a new
problem and a new opportunity. The new problem is that this index, measured in
rupees per liter of milk, is in many cases simultaneously determined with
profits per liter. Thus, profit per liter depends on environmental mitigation
expenditures, but environmental mitigation expenditures are also influenced by
profit. The new opportunity is the solution to the econometric problem; this is
to create an instrumental variable for environmental mitigation by regressing
it on a series of exogenous determinants of environmental mitigation.
Opportunity lies in the insights that this also gives into why some farms are
prone to spend more on environmental mitigation than others.
Among the factors accounted for in this study that might influence
the difference in the amount of environmental mitigation expenditure across
farms are differences across farms in access to assets and information
(transactions costs), other farm characteristics such as location, and policy
subsidies. Examples of such variables included in the analysis in this study
are education, experience, and age; access to credit; access to radio,
television, and newspapers; land tenure; membership in organizations; scale
dummy; distance to nearest market; and dummies for other locational variables.
The
measurement of environmental mitigation by the procedure above is only one
approach to measuring the important environmental impact of livestock. It was
motivated by the need to incorporate environmental factors in the analysis of
efficiency. However, more direct measures of environmental impact are possible
outside this framework. The next section explores a methodology for directly
assessing the interaction of animal density and environment.
3.4
A More Direct Approach: Mass Balance Calculations
A proper application rate is the principal manure management practice
affecting the potential contamination of water resources by manure nutrients
and, in fact, has very little to do with manure management technology per se.
Using the above approach to look at the effect on profitability of various
efforts to mitigate environmental problems, however, says little about the
effectiveness of these measures or whether they are necessary. To know the
latter, one would have to actually follow the nutrient chain from each
household to the final uptake of the nutrient by some source. Furthermore, to
ensure that the actual uptake was occurring, one would have to do specific
measurements of the disposal of the nutrients and the uptake. As noted above,
this is beyond the ability of the project to address.
However, it is possible to estimate from the household survey
described in Chapter 4 the potential of the externality in terms of a farm's
ability to utilize all the nutrients it produces. If the manure produced
exceeds the potential for on-farm use, then the farmer needs to (1) sell the
manure, (2) transport the manure to an area where there is enough land for
application, or (3) use a processing technology to transform the manure into a
product amenable to profitable long-distance transportation or produces a
product that eliminates the need for transportation. This may help us
understand why some farms may be investing more money in manure mitigation
technology than others, and it may also help us understand differences across
size of operations, particularly if large farms have limited land to dispose of
manure.
To
see whether a farmer has the ability to use all manure on his own farm, we
calculate the farm balance of manure nutrients relative to the farm's potential
to use the nutrients through crop production based on the farm-level data
collected in the household survey. From these numbers, the amount of nutrients
in the manure is estimated in terms of organic nitrogen (N) and phosphate (P2O5).
These two nutrients were chosen because they are the nutrients for which
regulations are primarily written, assuming that there is any regulation at
all. The amount of chemical fertilizer applied per land unit was also included,
when available, to compute the mass balance of nutrients applied to the land.
Crop assimilation capacity was estimated to determine whether a crop could
assimilate all the nutrients produced on farm. Next, the amount of manure sold
off-farm, if any, was subtracted.
Nutrient values from dairy cows were calculated. Given that the
level of nutrients may differ by species based on what is eaten, the amount of
nutrients for each species also differs.
Different countries have different conversions/limits. For
instance, according to the European Community Directive, the number of
manure-producing animals per hectare of land is limited to two dairy cows or
four ground stock/beef cattle. This is equivalent to a limit of 170 kg/ha/yr of
total nitrogen (including that deposited while grazing) in zones deemed
vulnerable to nitrate leaching (Williams, 1992). It is expected that the above
conversion factor will be lower for many of the developing countries, since the
amount of nitrogen and phosphate excreted in animal manure depends on diet,
species, and age of animal (Faassen and van Dijk, 1987).
3.4.2 Total nutrient production
From
animal unit estimations, the total nutrient deposition from dairy cows for each
household is estimated where the total nutrient deposited by household h was
the sum of the nutrient produced by dairy cows in household h. If data on
commercial fertilizer use were available, they were added to this calculations
to come up with total on-farm nutrient use, which would include both organic
and inorganic nutrients using the following formula:
h = household
AUh = number of dairy cows in household h
an = amount of nutrient n produced per dairy cow
3.4.3
Estimation of Crop Uptake
The capacity to use these nutrients at the household level is
estimated assuming that all the available land was planted with crop that would
take up the nutrients. This is done to determine whether a household would have
the potential to use all the nutrients produced given its current number of
animals.[69]
The capacity for each household to use the nutrients produced by
dairy operations is computed as area of cropland available to the household
multiplied by the nutrient uptake of the crops planted on the land. To
determine this, we calculated the potential for rice to take up these nutrients
under the assumption that all the available cropland was planted with rice. For
the purpose of the calculation, we assumed that the nitrogen uptake for rice
production is 100 kg per hectare and the phosphorous uptake is 32 kg per
hectare. It is recognized again that the actual figure will depend on the type
of soil and the ability of the soil to use nutrients, and that tropical soils
require far more nutrients than other types.
3.4.4 Mass Balance
In
order to determine the nutrient balance on the farm, the difference between
manure nutrient production and consumption is calculated. The mass balance (MB)
for each nutrient of interest (nitrogen and phosphorous) is expressed by the
following equation:
where:
Ah = area of cropland on household h
bn = absorptive capacity for nutrient n per unit of land
Tn = total nutrient uptake of rice
The
result is indicative of a household's potential assimilative capacity of
nutrients based on the current number of dairy cows on their property. A
positive MB would imply that there is sufficient land to assimilate the
nutrients produced, while a negative MB suggests that there is not enough land
to absorb them.
Although manure is a potentially valuable fertilizer and soil
conditioner, areas with concentrated livestock production may not have adequate
cropland for nutrient utilization stemming from by-products of livestock.
Therefore, exporting nutrients from concentrated areas to surrounding areas may
be both environmentally and economically beneficial. Markets for dairy manure seem to exist
in India. Manure produced by dairy cows raised in pastures was collected and
sold. Though there may be a market for manure, the market for unprocessed
manure may be seasonal, as crops need fertilizer only at certain periods of
their growing cycle.
To see if the households in this study that do not have the
ability to absorb all the nutrients on their own farms are getting rid of
excess nutrients through the market, we subtract what is sold or given away
from what is produced. We then compare the results across different-size
operations to see how different-size producers are handling the potential
problem.
[68] The
log-likelihood function of this model is presented in the appendix of Battese
and Coelli (1993). Estimation of the likelihood function also requires the
specification of a relationship among the variance parameters such that g = var(µit)/[var(vi)
+ var(µit)], where the parameter g has value between 0 and 1.
[69] It is recognized that in this analysis the ability of the household to absorb on all land overestimates what can be absorbed. Unfortunately, it is necessary to use this estimate, as most of the surveys are not detailed enough to differentiate crop acreage from building area. |
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