AUDPC_2_points: Estimate disease progress curve from only two points

In AlvesKS/epifitter: Analysis and Simulation of Plant Disease Progress Curves

Estimate disease progress curve from only two points

Description

Estimates area under the disease progress curve AUDPC from two qualifications only, see Jeger and Viljanen-Rollinson (2001) for more.

Usage

AUDPC_2_points(time, y0, yT)

Arguments

time	Number of days from first disease assessment to last disease assessment.
y0	A numeric value representing the disease intensity at the first intensity measurement. Must be greater than zero and less than one.
yT	A numeric value representing the disease intensity at the last intensity measurement. Must be greater than y0 and less than one.

Author(s)

Adam H. Sparks, [e-mail]

References

Jeger, M. J., & Viljanen-Rollinson, S. L. H. (2001). The use of the area under the disease-progress curve (AUDPC) to assess quantitative disease resistance in crop cultivars. *Theoretical and Applied Genetics*, 102, 32-40. DOI: 10.1007/s001220051615.

Examples

epi <- sim_logistic(N = 30, y0 = 0.01, dt = 5, r = 0.3, alpha = 0.5, n = 1)

# compare with use values from `epi`, first and last only
# time
epi$time[7]

# y0
epi$y[1]

# yT
epi$y[7]

AUDPC_2_points(time = epi$time[7], y0 = epi$y[1], yT = epi$y[7])

# compare with traitional AUDPC trapezoidal method
AUDPC(time = epi$time, y = epi$y, y_proportion = TRUE)

AlvesKS/epifitter documentation built on Jan. 26, 2025, 3:23 a.m.