The bound a family carries before it has seen a response

A family object built outside frmtmb::frm() has no data, so it has no fastest response and no bound. That state is not neutral, and this is the seam entry that settles it, so that a family which reaches ndt_bound_attach() at CONSTRUCTION is in one of two honest states rather than carrying whatever link its constructor happened to declare.

Usage

ndt_bound_pending(max_ndt = NULL, what = "ndt_bound()")

Arguments

max_ndt

An absolute bound in the response's own units, or NULL for the pending state.

what

The family's name, for the refusals.

Value

An object of class "frmtmb_eam_ndt_bound".

Details

• max_ndt = NULL gives a PENDING bound. The ndt link then refuses by name until frmtmb::frm() settles it. That refusal is load-bearing rather than decorative: frmtmb::mixture() never finalizes its components, so a component with an unsettled bound would read ndt on a scale nothing had set; and bf(ndt = ) runs linkfun() at PARSE time, where the range check is against whichever link the family is carrying, so a constant outside the SETTLED bound passes a check against a placeholder and reaches the objective as NaN.

• max_ndt = <a number> gives a SETTLED bound, and the family scores outside frm(): ndt is a time measured against that bound, frm_linpred(dpar = "ndt", type = "response") reports seconds, and a pinned constant means what it says.

The second is what a package reaching into another family's density slot needs, and it is what wiener(), lba(), rdm() and wiener_gng() do for themselves through their own max_ndt argument.

See also

ndt_bound() for the bound derived once the response is in hand, ndt_bound_attach() to put either on a family.

Examples

ndt_bound_pending()[["pending"]]
#> [1] TRUE
ndt_bound_pending(0.4)[["ub"]]
#> [1] 0.4