lppl_estimate_rob_1s: 1st step LPPL estimation procedure by Geraskin and Fantazzini...

Description Usage Arguments Details Value

View source: R/LPPL_3step.R

Description

This function performs the 1st step of the LPPL estimation procedure by Geraskin and Fantazzini (2013) and Fantazzini (2016)

Usage

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lppl_estimate_rob_1s(
  x,
  par_start = c(bet = 0.5, ome = 6, A = log(x[NROW(x)]), B = 0, C1 = 0, C2 = 0),
  max.win.tc = 0.1
)

Arguments

x

is a T x 1 data vector

par_start

is a 6 x 1 vector of starting values for the parameters to be estimated

max.win.tc

is a scalar setting the max window size (in percentage terms) used to fix the critical time tc in this estimation step

Details

This function performs the 1st step of the LPPL estimation procedure by Geraskin and Fantazzini (2013) and Fantazzini (2016) using the LPPL formula by Filimonov and Sornette (2013): The critical time tc is fixed at tc = t2 + 0.1 x (t2-t1), where t2 and t1 are the last and the first observation of the estimation sample, respectively. The remaining LPPL parameters [A, B, C1, C2, beta, omega] are estimated by using a quasi-Newton method algorithm. The starting values for the parameter vector is given by:

par_start[1] = beta

par_start[2] = omega

par_start[3] = A

par_start[4] = B

par_start[5] = C1

par_start[6] = C2

Value

par_est1 is a 6 x 1 vector of estimated parameters


deanfantazzini/bubble documentation built on Oct. 22, 2020, 2:43 p.m.