SI2_onepop: Flowering synchrony index of Augspurger (1983) in a...

In flower: Tools for characterizing flowering traits

Description

It measures the extent of overlapping in the flowering periods among pairs of individuals in a population.

Usage

SI2_onepop(dd, ind)

Arguments

dd	Flowering data
ind	ID of individual or inflorescence.

Details

si=(1/(n-1))*(1/fi)sum(ej);(j=1:n)

Value

n	The number of individuals in the population.
fi	The number of days individual i was flowering.
ej	The number of days that individuals i and j are flowering synchronously, with j != i.
bij	Number of days on which at least one of them (j and/or i) is flowering.
si	Synchrony index,from 0 (total lack of synchrony) to 1 (perfect synchrony).

Note

SI2 has been criticized for its dependence on flowering duration because the factor 1/fi increases the level of synchrony when flowering duration decreases.

Author(s)

WANG,XIE

References

[1]Augspurger, C. K. (1983). Phenology, flowering synchrony and fruit set of six neotropical shrubs. Biotropica 15: 257~267.

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(0,0,0,1,1,0,1)
ind=c("1","1","2","2")
dd=rbind(a1,a2,a3,a4)
colnames(dd)=c("D5/1","D5/2","D5/3","D5/4","D5/5","D5/6","D5/7")
C=SI2_onepop(dd,ind)
C

Example output

   si
1 0.5
2 0.5
   si
1 0.5
2 0.5

flower documentation built on May 1, 2019, 9:27 p.m.