# Tests for the bpbounds package # 2018-10-23 Tom Palmer if (!requireNamespace("tidyr", quietly = TRUE)) { install.packages("tidyr", repos = "https://cloud.r-project.org/") } context("Tests for bpbounds package") # Balke and Pearl, JASA, 1997 examples ---- ## Table 1 - note 9665 should be 9663 from paper ---- tab1dat <- data.frame( z = c(0, 0, 1, 1, 1, 1, 0, 0), x = c(0, 0, 0, 0, 1, 1, 1, 1), y = c(0, 1, 0, 1, 0, 1, 0, 1), freq = c(74, 11514, 34, 2385, 12, 9665, 0, 0) ) tab1inddat <- tidyr::uncount(tab1dat, freq) xt <- xtabs(~ x + y + z, data = tab1inddat) p <- prop.table(xt, margin = 3) ## Error checks test_that("Errors", { expect_error(bpbounds(p, fmt = "bivariate")) expect_error(bpbounds(p, fmt = "anything-you-like")) }) ## Analyses test_that("Balke and Pearl Table 1 example: trivariate data with 2 category instrument", { # Using conditional probabilities bpres <- bpbounds(p) expect_equal(class(bpres), "bpbounds") expect_equal(bpres$fmt, "trivariate") expect_equal(bpres$nzcats, 2) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1946, tol = 1e-4) expect_equal(bpres$bpub, 0.0054, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7990, tol = 1e-4) expect_equal(bpres$p11upp, 0.9990, tol = 1e-4) expect_equal(bpres$crrlb, 0.8042, tol = 1e-4) expect_equal(bpres$crrub, 1.0054, tol = 1e-4) expect_true(bpres$monoinequality) expect_equal(bpres$monobplb, -0.1946, tol = 1e-4) expect_equal(bpres$monobpub, 0.0054, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7990, tol = 1e-4) expect_equal(bpres$monop11upp, 0.9990, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8042, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0054, tol = 1e-4) print(bpres) print(bpres, digits = 4) bpres sbp = summary(bpres) expect_equal(class(sbp), "summary.bpbounds") print(sbp) sbp print(sbp, digits = 2) print(sbp, digits = 4) # Using cell counts bpres = bpbounds(xt) expect_equal(class(bpres), "bpbounds") expect_equal(bpres$fmt, "trivariate") expect_equal(bpres$nzcats, 2) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1946, tol = 1e-4) expect_equal(bpres$bpub, 0.0054, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7990, tol = 1e-4) expect_equal(bpres$p11upp, 0.9990, tol = 1e-4) expect_equal(bpres$crrlb, 0.8042, tol = 1e-4) expect_equal(bpres$crrub, 1.0054, tol = 1e-4) expect_true(bpres$monoinequality) expect_equal(bpres$monobplb, -0.1946, tol = 1e-4) expect_equal(bpres$monobpub, 0.0054, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7990, tol = 1e-4) expect_equal(bpres$monop11upp, 0.9990, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8042, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0054, tol = 1e-4) }) ## Test the bivariate formulation ---- g = xtabs(~ y + z, data = tab1inddat) gp = prop.table(g, margin = 2) t = xtabs(~ x + z, data = tab1inddat) tp = prop.table(t, margin = 2) test_that("Balke and Pearl Table 1 example treated as bivariate data", { bpres = bpbounds(p = gp, t = tp, fmt = "bivariate") expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1974, tol = 1e-4) expect_equal(bpres$bpub, 0.0064, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7962, tol = 1e-4) expect_equal(bpres$p11upp, 1, tol = 1e-4) expect_equal(bpres$crrlb, 0.8013, tol = 1e-4) expect_equal(bpres$crrub, 1.0064, tol = 1e-4) expect_true(bpres$monoinequality) expect_equal(bpres$monobplb, -0.1974, tol = 1e-4) expect_equal(bpres$monobpub, 0.0064, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7962, tol = 1e-4) expect_equal(bpres$monop11upp, 1, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8013, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0064, tol = 1e-4) sbp = summary(bpres) print(sbp, digits = 3) print(sbp) }) test_that("Balke and Pearl, bivariate data using cell counts", { bpres <- bpbounds(p = g, t = t, fmt = "bivariate") expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1974, tol = 1e-4) expect_equal(bpres$bpub, 0.0064, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7962, tol = 1e-4) expect_equal(bpres$p11upp, 1, tol = 1e-4) expect_equal(bpres$crrlb, 0.8013, tol = 1e-4) expect_equal(bpres$crrub, 1.0064, tol = 1e-4) expect_true(bpres$monoinequality) expect_equal(bpres$monobplb, -0.1974, tol = 1e-4) expect_equal(bpres$monobpub, 0.0064, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7962, tol = 1e-4) expect_equal(bpres$monop11upp, 1, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8013, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0064, tol = 1e-4) sbp <- summary(bpres) print(sbp, digits = 3) print(sbp) }) test_that("Bivariate data with cell counts for one and cond probs other", { bpres <- bpbounds(p = gp, t = t, fmt = "bivariate") sbp <- summary(bpres) expect_equal(class(bpres), "bpbounds") expect_equal(bpres$fmt, "bivariate") expect_equal(bpres$nzcats, 2) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1974, tol = 1e-4) expect_equal(bpres$bpub, 0.0064, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7962, tol = 1e-4) expect_equal(bpres$p11upp, 1, tol = 1e-4) expect_equal(bpres$crrlb, 0.8013, tol = 1e-4) expect_equal(bpres$crrub, 1.0064, tol = 1e-4) expect_true(bpres$inequality) expect_equal(bpres$monobplb, -0.1974, tol = 1e-4) expect_equal(bpres$monobpub, 0.0064, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7962, tol = 1e-4) expect_equal(bpres$monop11upp, 1, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8013, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0064, tol = 1e-4) }) ## Balke and Pearl, 1997, Table 2 - 0.001 was 0 in published table ---- tab2cp <- c(.0064, 0, .9936, 0, .0028, 0.001, .1972, .799) p2 <- array(tab2cp, dim = c(2, 2, 2), dimnames = list( x = c(0, 1), y = c(0, 1), z = c(0, 1) )) p2 <- as.table(p2) sum(p2) test_that("Balke and Pearl Table 2 example: trivariate data with 2 category instrument", { bpres <- bpbounds(p2, fmt = "trivariate") sbp <- summary(bpres) print(sbp) expect_equal(class(bpres), "bpbounds") expect_equal(bpres$fmt, "trivariate") expect_equal(bpres$nzcats, 2) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.1946, tol = 1e-4) expect_equal(bpres$bpub, 0.0054, tol = 1e-4) expect_equal(bpres$p10low, 0.9936, tol = 1e-4) expect_equal(bpres$p10upp, 0.9936, tol = 1e-4) expect_equal(bpres$p11low, 0.7990, tol = 1e-4) expect_equal(bpres$p11upp, 0.9990, tol = 1e-4) expect_equal(bpres$crrlb, 0.8042, tol = 1e-4) expect_equal(bpres$crrub, 1.0054, tol = 1e-4) expect_true(bpres$monoinequality) expect_equal(bpres$monobplb, -0.1946, tol = 1e-4) expect_equal(bpres$monobpub, 0.0054, tol = 1e-4) expect_equal(bpres$monop10low, 0.9936, tol = 1e-4) expect_equal(bpres$monop10upp, 0.9936, tol = 1e-4) expect_equal(bpres$monop11low, 0.7990, tol = 1e-4) expect_equal(bpres$monop11upp, 0.9990, tol = 1e-4) expect_equal(bpres$monocrrlb, 0.8042, tol = 1e-4) expect_equal(bpres$monocrrub, 1.0054, tol = 1e-4) }) # Meleady AJCN 2003; 3 category instrument - Table 3 of paper ---- dat <- data.frame( count = c(341, 47, 297, 17, 63, 18, 272, 41, 269, 38, 56, 35), z = c(0, 0, 1, 1, 2, 2, 0, 0, 1, 1, 2, 2), y = c(0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1), x = c(0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1) ) longdat <- tidyr::uncount(dat, weights = count) ## Trivariate data xt3 <- xtabs(count ~ x + y + z, data = dat) p3 <- prop.table(xt3, margin = 3) test_that("Mendelian randomization with 3 category instrument, trivariate data", { bpres <- bpbounds(p3) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.3101, tol = 1e-4) expect_equal(bpres$bpub, 0.4622, tol = 1e-4) expect_equal(bpres$p10low, 0.4332, tol = 1e-4) expect_equal(bpres$p10upp, 0.5136, tol = 1e-4) expect_equal(bpres$p11low, 0.2035, tol = 1e-4) expect_equal(bpres$p11upp, 0.8953, tol = 1e-4) expect_equal(bpres$crrlb, 0.3962, tol = 1e-4) expect_equal(bpres$crrub, 2.0670, tol = 1e-4) expect_false(bpres$monoinequality) sbp <- summary(bpres) print(sbp) }) ## Bivariate data gtab <- xtabs(~ y + z, data = longdat) gp <- prop.table(gtab, margin = 2) gp ttab <- xtabs(~ x + z, data = longdat) tp <- prop.table(ttab, margin = 2) tp test_that("Mendelian randomization with 3 category instrument, bivariate data", { bpres <- bpbounds(p = gp, t = tp, fmt = "bivariate") print(bpres) expect_true(bpres$inequality) expect_equal(bpres$bplb, -0.5720, tol = 1e-4) expect_equal(bpres$bpub, 0.5942, tol = 1e-4) expect_equal(bpres$p10low, 0.4058, tol = 1e-4) expect_equal(bpres$p10upp, 0.5720, tol = 1e-4) expect_equal(bpres$p11low, 0, tol = 1e-4) expect_equal(bpres$p11upp, 1, tol = 1e-4) expect_equal(bpres$crrlb, 0, tol = 1e-4) expect_equal(bpres$crrub, 2.4643, tol = 1e-4) expect_false(bpres$monoinequality) sbp <- summary(bpres) print(sbp) }) # GitHub issue #3: IV inequality with 3 category instrument ---- # The reporter applied rowSums(apply(tabp, c(1,2), max)) as the IV inequality check, # which is only valid for a binary instrument. The correct inequalities for a # 3-category instrument are the Ramsahai constraints implemented in A_tri_x2y2z3. test_that("Issue 3, example 1: inequality correctly detected as satisfied", { # This table is compatible with a valid IV model: a joint distribution over # the 8 compliance types and 4 response types exists that reproduces it # exactly (verified by linear programming), so all Ramsahai constraints # hold. Versions <= 0.1.7 wrongly reported a violation because the panels # of p were fed to A_tri_x2y2z3 in the wrong within-panel order. tabp <- as.table(array( data = c(0.5279183, 0.02208171, 0.1220817, 0.3279183, 0.0849975, 0.3150025, 0.4650025, 0.1349975, 0.1132796, 0.3867204, 0.1867204, 0.3132796), dim = c(2, 2, 3), dimnames = list(x = c(0, 1), y = c(0, 1), z = c(0, 1, 2)) )) bpres <- bpbounds(tabp) expect_true(bpres$inequality) }) test_that("Issue 3, example 2 (vignette MR data): inequality correctly not violated", { # Reporter expected inequality = FALSE based on rowSums(apply(p3, c(1,2), max)) = 1.08, # but this is not a valid IV inequality check for a 3-category instrument. # All Ramsahai constraints are satisfied for this dataset. bpres <- bpbounds(p3) expect_true(bpres$inequality) }) # Trivariate data, 3 category instrument, monotonicity bounds ---- # Constructed from an explicit IV model with monotone compliance: # compliance types never/(z=2 only)/(z=1,2)/always with probabilities # 0.4/0.3/0.2/0.1 and response types (y0,y1) = (0,0)/(1,0)/(0,1)/(1,1) with # probabilities 0.3/0.2/0.4/0.1, independent of each other. Hence # P(Y=1|do(X=0)) = 0.3, P(Y=1|do(X=1)) = 0.5, and the true ACE = 0.2. test_that("Trivariate 3 category instrument monotonicity bounds", { cpm <- c(0.63, 0.05, 0.27, 0.05, 0.49, 0.15, 0.21, 0.15, 0.28, 0.30, 0.12, 0.30) tabm <- as.table(array( cpm, dim = c(2, 2, 3), dimnames = list(x = c(0, 1), y = c(0, 1), z = c(0, 1, 2)) )) bpres <- bpbounds(tabm) expect_true(bpres$inequality) expect_true(bpres$monoinequality) # mlow = p112 + p000 - 1; mupp = 1 - p100 - p012 expect_equal(bpres$monobplb, -0.07, tol = 1e-8) expect_equal(bpres$monobpub, 0.43, tol = 1e-8) expect_equal(bpres$monop10low, 0.27, tol = 1e-8) expect_equal(bpres$monop10upp, 0.37, tol = 1e-8) expect_equal(bpres$monop11low, 0.30, tol = 1e-8) expect_equal(bpres$monop11upp, 0.70, tol = 1e-8) expect_equal(bpres$monocrrlb, 0.30 / 0.37, tol = 1e-8) expect_equal(bpres$monocrrub, 0.70 / 0.27, tol = 1e-8) # bounds must contain the true causal quantities of the generating model expect_true(bpres$monobplb <= 0.2 && 0.2 <= bpres$monobpub) expect_true(bpres$monop10low <= 0.3 && 0.3 <= bpres$monop10upp) expect_true(bpres$monop11low <= 0.5 && 0.5 <= bpres$monop11upp) }) # CRR bounds reported as NA when unbounded ---- test_that("CRR bound is NA with a note when P(Y|do(X=0)) lower bound is 0", { g <- as.table(array(c(.9, .1, .8, .2), dim = c(2, 2), dimnames = list(y = 0:1, z = 0:1))) t <- as.table(array(c(.5, .5, .4, .6), dim = c(2, 2), dimnames = list(x = 0:1, z = 0:1))) bpres <- bpbounds(p = g, t = t, fmt = "bivariate") expect_true(bpres$inequality) expect_true(bpres$monoinequality) expect_equal(bpres$p10low, 0) expect_true(is.na(bpres$crrub)) expect_true(is.na(bpres$monocrrub)) expect_equal(bpres$crrlb, 0) expect_output(print(summary(bpres)), "CRR bounds reported as NA are unbounded") }) ## More error checks test_that("Cond probs and 1 cell count error", { cpr <- c(.0064, 0, .9936, 0, .0028, .001, .1972, 20) tabpr <- as.table(array( cpr, dim = c(2, 2, 2), dimnames = list( x = c(0, 1), y = c(0, 1), z = c(0, 1) ) )) expect_error(bpbounds(tabpr)) }) test_that("Cond probs and 1, giving cond probs sum error", { cpr <- c(.0064, 0, .9936, 0, .0028, .001, .1972, 1) tabpr <- array(cpr, dim = c(2, 2, 2), dimnames = list( x = c(0, 1), y = c(0, 1), z = c(0, 1) )) |> as.table() expect_error(bpbounds(tabpr)) }) test_that("Cell counts and one cond prob", { cpr <- c(640, 0, 9936, 0, 28, 1, 1972, 0.5) tabpr <- array(cpr, dim = c(2, 2, 2), dimnames = list( x = c(0, 1), y = c(0, 1), z = c(0, 1) )) |> as.table() expect_error(bpbounds(tabpr)) })