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| C1   | R Documentation   |
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Six Herbicide Data Sets
-----------------------

Description
~~~~~~~~~~~

The ``C1``–``C4``, ``M2`` and ``M4`` data frames have 40 to 72 rows and
three columns.

Six bioassay on the action of the herbicides chlorsulfuron and
metsulfuron methyl on the callus area of colonies of *Brassica napus L*.
The experiments consist of measurements for different dose levels and
can be balanced (``C4``, ``M2``) or unbalanced (``C1``, ``C2``, ``C3``,
``M4``).

Usage
~~~~~

::

      data(C1)
      data(C2)
      data(C3)
      data(C4)
      data(M2)
      data(M4)

Format
~~~~~~

These data frame contain the following columns:

``group``
    indicator variable for each tested dose;

``dose``
    the tested dose (nmol/l);

``area``
    the callus area (*mm^2*).

Note
~~~~

Data sets ``C3`` and ``chlorsulfuron`` are the same. Data sets ``M2``
and ``metsulfuron`` are the same.

Source
~~~~~~

The data were obtained from

Seiden, P., Kappel, D. and Streibig, J. C. (1998) Response of *Brassica
napus L.* tissue culture to metsulfuron methyl and chlorsulfuron. *Weed
Research*, **38**, 221–228.

References
~~~~~~~~~~

Bellio, R., Jensen, J.E. and Seiden, P. (2000). Applications of
likelihood asymptotics for nonlinear regression in herbicide bioassays.
*Biometrics*, **56**, 1204–1212.

Brazzale, A. R. (2000) *Practical Small-Sample Parametric Inference*.
Ph.D. Thesis N. 2230, Department of Mathematics, Swiss Federal Institute
of Technology Lausanne. Section 5.3, Example 8.

See Also
~~~~~~~~

``chlorsulfuron``, ``metsulfuron``

Examples
~~~~~~~~

::

    data(C3)
    attach(C3)
    plot(dose, area, xlab = "tested dose (nmol/l)", 
         ylab = "log callus area (mm^2)", log = "y")
    detach()

