poolpower_t function

Visualize T-test Power for Pooling Design

Useful for assessing efficiency gains that might be achieved with a pooling design.

poolpower_t(g = c(1, 3, 10), d = NULL, mu1 = NULL, mu2 = NULL,
  sigsq = NULL, sigsq1 = sigsq, sigsq2 = sigsq, sigsq_p = 0,
  sigsq_m = 0, multiplicative = FALSE, alpha = 0.05, beta = 0.2,
  assay_cost = 100, other_costs = 0, labels = TRUE)

Arguments

• g: Numeric vector of pool sizes to include.
• d: Numeric value specifying true difference in group means.
• mu1, mu2: Numeric value specifying group means. Required if multiplicative = TRUE.
• sigsq: Numeric value specifying the variance of observations.
• sigsq1, sigsq2: Numeric value specifying the variance of observations for each group.
• sigsq_p: Numeric value specifying the variance of processing errors.
• sigsq_m: Numeric value specifying the variance of measurement errors.
• multiplicative: Logical value for whether to assume multiplicative rather than additive errors.
• alpha: Numeric value specifying type-1 error rate.
• beta: Numeric value specifying type-2 error rate.
• assay_cost: Numeric value specifying cost of each assay.
• other_costs: Numeric value specifying other per-subject costs.
• labels: Logical value.

Returns

Plot of power vs. total costs generated by ggplot.

Examples

# Plot power vs. total study costs for d = 0.25, sigsq = 1, and costs of $100
# per assay and $0 in other per-subject costs.
poolpower_t(d = 0.5, sigsq = 1, assay_cost = 100, other_costs = 0)

# Repeat but with $10 in per-subject costs.
poolpower_t(d = 0.5, sigsq = 1, assay_cost = 100, other_costs = 10)

# Back to no per-subject costs, but with processing and measurement error
poolpower_t(d = 0.5, sigsq = 1, sigsq_p = 0.2, sigsq_m = 0.1,
            assay_cost = 100, other_costs = 0)