Compare a proposed survey cost against the EVPI or EVSI

Prints a plain-language recommendation: if the survey costs less than the VOI, information is worth collecting; otherwise proceed without it.

Usage

survey_worth_it(result, survey_cost, outcome_name = NULL)

Arguments

result

A completed voi_problem object (after calculate_value_info()), or a scalar VOI value.

survey_cost

Numeric. The cost of the proposed survey in the same units as the VOI.

outcome_name

Character. Label for the outcome units.

Value

A list with $voi, $survey_cost, and $worth_it (logical), invisibly. The recommendation is printed automatically.

Examples

V <- matrix(c(55, 135, 100, 100), nrow = 2, byrow = TRUE)
p <- c(0.5, 0.5)
result <- calculate_evpi(V, p, outcome_name = "frogs")
#> ℹ VOI problem: 2 actions, 2 states, 2 experiment outcomes.
#> 
#> ── EVPI Summary ──
#> 
#> ── Decision table ──
#> 
#>    action state_1 state_2 EV_prior best_action?
#>  action_1      55     135       95             
#>  action_2     100     100      100          YES
#> ────────────────────────────────────────────────────────────────────────────────
#> ℹ Best action without survey: action_2
#> ℹ Expected outcome without survey: 100 frogs
#> ℹ Expected outcome with perfect information: 117.5 frogs
#> ✔ EVPI = 17.5 frogs
#> ────────────────────────────────────────────────────────────────────────────────
survey_worth_it(result, survey_cost = 10)
#> ────────────────────────────────────────────────────────────────────────────────
#> ✔ Survey cost (10 frogs) is LESS THAN the value of information (17.5 frogs).
#> ℹ Collecting information is worth it.
#> ────────────────────────────────────────────────────────────────────────────────