flower (version 1.0)

SI4: An alternative synchronization index of Marquis (1988)

Description

SI4 thus facilitates comparison between species irrespective of flowering duration.

Usage

SI4(dd, pop, ind)

Arguments

dd

Flowering data.

pop

ID of population.

ind

ID of individual.

Value

• si4
  An alternative synchronization index of Marquis (1988).
• xit
  The numbers of open flowers per day.
• bit
  The total number of flowers of individual i during the whole flowering period.
• pt
  The proportion of all marked stems (inflorescence or individual) in bloom at day t.
• t
  Day.

Details

si4=sum(xit/bit)*pt;bit=sum(xit);t=1:n

References

{[1]}{Marquis RJ. Phenologcal variation in the Neotropical understory shrub Piper arieianum: causes and consequences. Ecology. 1988;69:1552~1565.} {[2]}{Bolmgren K. The use of synchronization measures in studies of plant reproduction phenology. Oikos. 1998;82:411~415.}

See Also

nothing

Examples

a1=c(0,1,1,1,0,0,0)
a2=c(0,1,0,1,1,0,0)
a3=c(0,0,0,1,1,1,0)
a4=c(1,0,0,1,1,0,1)
a5=c(0,0,1,1,1,0,1)
a6=c(0,0,0,1,1,1,1)
pop=c("pop1","pop1","pop1","pop2","pop2","pop2")
ind=c(1,2,3,1,2,3)
dd=rbind(a1,a2,a3,a4,a5,a6)
colnames(dd)=c("D5/1","D5/2","D5/3","D5/4","D5/5","D5/6","D5/7")
C=SI4(dd,as.matrix(pop),as.matrix(ind))
C