Description Usage Arguments Details Value Warning Note Author(s) References See Also Examples
Using Data Envelopment Analysis (DEA), this function measures productivity and profitability in levels and changes with Laspeyres index.
The Laspeyres productivity index uses the previous period prices as aggregators.
Deflated shadow prices of inputs and outputs can also be computed.
1 2 3 4 5 6 7 | laspeyres(data, id.var, time.var, x.vars, y.vars, w.vars, p.vars, tech.change = TRUE,
tech.reg = TRUE, rts = c("vrs", "crs", "nirs", "ndrs"), orientation = c("out",
"in", "in-out"), parallel = FALSE, cores = max(1, detectCores() - 1), scaled = TRUE,
shadow = FALSE)
## S3 method for class 'Laspeyres'
print(x, digits = NULL, ...)
|
data |
A dataframe containing the required information for measuring productivity and profitability. |
id.var |
Firms' ID variable. Can be an integer or a text string. |
time.var |
Time period variable. Can be an integer or a text string. |
x.vars |
Input quantity variables. Can be a vector of text strings or integers. |
y.vars |
Output quantity variables. Can be a vector of text strings or integers. |
w.vars |
Input price variables. Can be a vector of text strings or integers. |
p.vars |
Output price variables. Can be a vector of text strings or integers. |
tech.change |
Logical. If |
tech.reg |
Logical. If |
rts |
Character string specifying the returns to scale assumption.
The default value is |
orientation |
Character string specifying the orientation.
The default value is |
parallel |
Logical. Allows parallel computation. If |
cores |
Integer. Used only if |
scaled |
Logical. If |
shadow |
Logical. Default is |
x |
An object of class |
digits |
The minimum number of significant digits to be printed in values.
Default = |
... |
Currently not used. |
When tech.change
is set to FALSE
, this overrides the effect of tech.reg
.
Setting scaled = FALSE
(no rescaling of data) may lead to numerical problems in solving LP
problems while optimizing DEA models. In extreme cases it may also prevent models from being optimized.
The Laspeyres index is not transitive and therefore each firm is compared to itself in the previous period.
Since there is no previous period for the first period, the results for this first period are replaced by NA
.
laspeyres()
returns a list of class 'Laspeyres'
for which a summary of productivity and profitability
measures in levels and changes, as well as a summary shadow prices (if shadow = TRUE
), is printed.
This list contains the following items:
Levels |
Several elements are provided, depending on the
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Changes |
Change indices of the different elements of | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Shadowp |
Returned only if |
From an object of class 'Laspeyres'
obtained from laspeyres()
, the
Levels
function extracts individual productivity and profitability levels;
Changes
function extracts individual productivity and profitability change indices; and
If shadow = TRUE
, the Shadowp
function extracts individual input and output deflated shadow prices.
The laspeyres()
function will not work with unbalanced panel data.
The Laspeyres index may be sensitive to the rescaling.
For extreme efficient observations, the problem of multiple solutions may arise and the values of shadow prices may differ depending on the linear programming solver used (here lpSolveAPI).
All output-oriented efficiency scores are computed a la Shephard, while all input-oriented efficiency scores are computed a la Farrell. Hence, all efficiency scores are greater than zero and are lower or equal to one.
K Herv<c3><a9> Dakpo, Yann Desjeux, Laure Latruffe
Coelli T.J., D.S.P. Rao, C.J. O'Donnell, and G.E. Battese (2005), An Introduction to Efficiency and Productivity Analysis. Springer Eds.
O'Donnell C.J. (2011), The sources of productivity change in the manufacturing sectors of the U.S. economy. School of Economics, University of Queensland, Australia. URL: http://www.uq.edu.au/economics/cepa/docs/WP/WP072011.pdf
See Levels
to retrieve a data frame with Laspeyres
productivity and profitability in levels and components.
See Changes
to retrieve a data frame with Laspeyres
productivity and profitability changes and components.
See Shadowp
to retrieve deflated input and output shadow prices, provided that shadow = TRUE
.
See also fisher
and paasche
for computation with alternative indices.
1 2 3 4 5 6 7 |
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