Hello,
 does anyone knows this predict is not resulting?

# lm predict
dfTestes3sitesCriptic$Velocity_corrected <- ifelse
(dfTestes3sitesCriptic$Season == "A" & dfTestes3sitesCriptic$BeforeAfter ==
"Before", (dfTestes3sitesCriptic$Velocity * mVel3ABefAfter), (ifelse
(dfTestes3sitesCriptic$Season == "Sp" & dfTestes3sitesCriptic$BeforeAfter ==
"Before", (dfTestes3sitesCriptic$Velocity  * mVel3SpBefAfter),
dfTestes3sitesCriptic$Velocity )))

dfTestes3sitesCriptic$Dens_min_corrected <- predict (lm(
dfTestes3sitesCriptic$Dens_min ~ dfTestes3sitesCriptic$Velocity,
dfTestes3sitesCriptic$Velocity_corrected))


just for help:
Code_Site Year Season YearSeason Type_Environment BeforeAfter Species_Group
31    PPBNoc 1998      A     1998-A    Criptobenthic      Before
Fish
33    PPBNoc 1999     Sp    1999-Sp    Criptobenthic      Before
Fish
35    PPBNoc 2009      A     2009-A    Criptobenthic       After
Fish
37    PPBNoc 2009     Sp    2009-Sp    Criptobenthic       After
Fish
39    PPBNoc 2010      A     2010-A    Criptobenthic       After
Fish
   TransectTime_min TransectLenght_m Area_m2 Number Density Velocity
Dens_min
31            15.00               55      55     89    1.62     3.67
5.93
33            15.00               55      55     50    0.91     3.67
3.33
35            18.15               45      45    185    4.11     2.48
10.20
37            10.23               45      45     92    2.04     4.40
9.00
39            16.92               45      45    251    5.58     2.66
14.84
   Code_Site2 Velocity_corrected
31       TRUE               2.58
33       TRUE               3.25
35       TRUE               2.48
37       TRUE               4.40
39       TRUE               2.66



Thanks a lot.
Barbara

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