

   TTooxxiicciittyy ooff NNiittrrooffeenn iinn AAqquuaattiicc SSyysstteemmss

   AArrgguummeennttss::

       conc: The nitrofen concentration in the solution
             (mug/litre).

     brood1: The number of live offspring in the first brood.

     brood2: The number of live offspring in the second brood.

     brood3: The number of live offspring in the third brood.

      total: The total number of live offspring in the first
             three broods.

   SSUUMMMMAARRYY::

        The `nitrofen' data frame has 50 rows and 5 columns.

        Nitrofen is a herbicide that was used extensively for
        the control of broad-leaved and grass weeds in cereals
        and rice. Although it is relatively non-toxic to adult
        mammals, nitrofen is a significant tetragen and muta-
        gen.  It is also acutely toxic and reproductively toxic
        to cladoceran zooplankton.  Nitrofen is no longer in
        commercial use in the U.S., having been the first pes-
        ticide to be withdrawn due to tetrogenic effects.

        The data here come from an experiment to measure the
        reproductive toxicity of nitrofen on a species of zoo-
        plankton (Ceriodaphnia dubia).  50 animals were random-
        ized into batches of 10 and each batch was put in a
        solution with a measured concentration of nitrofen.
        Then the number of live offspring in each of the three
        broods to each animal was recorded.

   DDAATTAA DDEESSCCRRIIPPTTIIOONN::

        This data frame contains the following columns:

   SSOOUURRCCEE::

        The data were obtained from

        Bailer, A.J. and Oris, J.T. (1994) Assessing toxicity
        of pollutants in aquatic systems. In Case Studies in
        Biometry. N. Lange, L. Ryan, L. Billard, D. Brillinger,
        L. Conquest and J. Greenhouse (editors), 25-40. John
        Wiley.

   OOTTHHEERR RREEFFEERREENNCCEESS::

        Davison, A.C. and Hinkley, D.V. (1997) Bootstrap Meth-
        ods and Their Application. Cambridge University Press.

