#----------------------------------------------# # Author: Laurent Berge # Date creation: Fri Jul 10 09:03:06 2020 # ~: package sniff tests #----------------------------------------------# # Not everything is currently covered, but I'll improve it over time # Some functions are not trivial to test properly though library(fixest) test = fixest:::test ; chunk = fixest:::chunk vcovClust = fixest:::vcovClust setFixest_notes(FALSE) if(fixest:::is_r_check()){ if(requireNamespace("data.table", quietly = TRUE)){ library(data.table) data.table::setDTthreads(1) } setFixest_nthreads(1) } #### #### ESTIMATIONS #### #### #### #### ... Main #### #### chunk("ESTIMATION") set.seed(0) base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$fe_2 = rep(1:5, 30) base$fe_3 = sample(15, 150, TRUE) base$constant = 5 base$y_int = as.integer(base$y) base$w = as.vector(unclass(base$species) - 0.95) base$offset_value = unclass(base$species) - 0.95 base$y_01 = 1 * ((scale(base$x1) + rnorm(150)) > 0) # what follows to avoid removal of fixed-effects (logit is pain in the neck) base$y_01[1:5 + rep(c(0, 50, 100), each = 5)] = 1 base$y_01[6:10 + rep(c(0, 50, 100), each = 5)] = 0 # We enforce the removal of observations base$y_int_null = base$y_int base$y_int_null[base$fe_3 %in% 1:5] = 0 for(model in c("ols", "pois", "logit", "negbin", "Gamma")){ cat("Model: ", format(model, width = 6), sep = "") for(use_weights in c(FALSE, TRUE)){ my_weight = NULL if(use_weights) my_weight = base$w for(use_offset in c(FALSE, TRUE)){ my_offset = NULL if(use_offset) my_offset = base$offset_value for(id_fe in 0:9){ cat(".") tol = switch(model, "negbin" = 1e-2, "logit" = 3e-5, 1e-5) # Setting up the formula to accommodate FEs if(id_fe == 0){ fml_fixest = fml_stats = y ~ x1 } else if(id_fe == 1){ fml_fixest = y ~ x1 | species fml_stats = y ~ x1 + factor(species) } else if(id_fe == 2){ fml_fixest = y ~ x1 | species + fe_2 fml_stats = y ~ x1 + factor(species) + factor(fe_2) } else if(id_fe == 3){ # varying slope fml_fixest = y ~ x1 | species[[x2]] fml_stats = y ~ x1 + x2:species } else if(id_fe == 4){ # varying slope -- 1 VS, 1 FE fml_fixest = y ~ x1 | species[[x2]] + fe_2 fml_stats = y ~ x1 + x2:species + factor(fe_2) } else if(id_fe == 5){ # varying slope -- 2 VS fml_fixest = y ~ x1 | species[x2] fml_stats = y ~ x1 + x2:species + species } else if(id_fe == 6){ # varying slope -- 2 VS bis fml_fixest = y ~ x1 | species[[x2]] + fe_2[[x3]] fml_stats = y ~ x1 + x2:species + x3:factor(fe_2) } else if(id_fe == 7){ # Combined clusters fml_fixest = y ~ x1 + x2 | species^fe_2 fml_stats = y ~ x1 + x2 + paste(species, fe_2) } else if(id_fe == 8){ fml_fixest = y ~ x1 | species[x2] + fe_2[x3] + fe_3 fml_stats = y ~ x1 + species + i(species, x2) + factor(fe_2) + i(fe_2, x3) + factor(fe_3) } else if(id_fe == 9){ fml_fixest = y ~ x1 | species + fe_2[x2,x3] + fe_3 fml_stats = y ~ x1 + species + factor(fe_2) + i(fe_2, x2) + i(fe_2, x3) + factor(fe_3) } # ad hoc modifications of the formula if(model == "logit"){ fml_fixest = xpd(y_01 ~ ..rhs, ..rhs = fml_fixest[[3]]) fml_stats = xpd(y_01 ~ ..rhs, ..rhs = fml_stats[[3]]) # The estimations are OK, conv differences out of my control if(id_fe %in% 8:9) tol = 0.5 } else if(model == "pois"){ fml_fixest = xpd(y_int_null ~ ..rhs, ..rhs = fml_fixest[[3]]) fml_stats = xpd(y_int_null ~ ..rhs, ..rhs = fml_stats[[3]]) } else if(model %in% c("negbin", "Gamma")){ fml_fixest = xpd(y_int ~ ..rhs, ..rhs = fml_fixest[[3]]) fml_stats = xpd(y_int ~ ..rhs, ..rhs = fml_stats[[3]]) } adj = 1 if(model == "ols"){ res = feols(fml_fixest, base, weights = my_weight, offset = my_offset) res_bis = lm(fml_stats, base, weights = my_weight, offset = my_offset) } else if(model %in% c("pois", "logit", "Gamma")){ adj = 0 if(model == "Gamma" && use_offset) next my_family = switch(model, pois = poisson(), logit = binomial(), Gamma = Gamma()) res = feglm(fml_fixest, base, family = my_family, weights = my_weight, offset = my_offset) if(!is.null(res$obs_selection$obsRemoved)){ qui = res$obs_selection$obsRemoved # I MUST do that.... => subset does not work... base_tmp = base[qui, ] base_tmp$my_offset = my_offset[qui] base_tmp$my_weight = my_weight[qui] res_bis = glm(fml_stats, base_tmp, family = my_family, weights = my_weight, offset = my_offset) } else { res_bis = glm(fml_stats, data = base, family = my_family, weights = my_weight, offset = my_offset) } } else if(model == "negbin"){ # no offset in glm.nb + no VS in fenegbin + no weights in fenegbin if(use_weights || use_offset || id_fe > 2) next res = fenegbin(fml_fixest, base, notes = FALSE) res_bis = MASS::glm.nb(fml_stats, base) } test(coef(res)["x1"], coef(res_bis)["x1"], "~", tol) test(se(res, se = "st", ssc = ssc(adj = adj))["x1"], se(res_bis)["x1"], "~", tol) test(pvalue(res, se = "st", ssc = ssc(adj = adj))["x1"], pvalue(res_bis)["x1"], "~", tol*10**(model == "negbin")) # cat("Model: ", model, ", FE: ", id_fe, ", weight: ", use_weights, ", offset: ", use_offset, "\n", sep="") } cat("|") } } cat("\n") } #### #### ... Corner cases #### #### chunk("Corner cases") # We test the absence of bugs base = iris names(base) = c("y", "x1", "x2", "x3", "fe1") base$fe2 = rep(1:5, 30) base$y[1:5] = NA base$x1[4:8] = NA base$x2[4:21] = NA base$x3[110:111] = NA base$fe1[110:118] = NA base$fe2[base$fe2 == 1] = 0 base$fe3 = sample(letters[1:5], 150, TRUE) base$period = rep(1:50, 3) base$x_cst = 1 res = feols(y ~ 1 | csw(fe1, fe1^fe2), base) res = feols(y ~ 1 + csw(x1, i(fe1)) | fe2, base) res = feols(y ~ csw(f(x1, 1:2), x2) | sw0(fe2, fe2^fe3), base, panel.id = ~ fe1 + period) res = feols(d(y) ~ -1 + d(x2), base, panel.id = ~ fe1 + period) test(length(coef(res)), 1) res = feols(c(y, x1) ~ 1 | fe1 | x2 ~ x3, base) res = feols(y ~ x1 | fe1[x2] + fe2[x2], base) # # NA models (ie all variables are collinear with the FEs) # # Should work when warn = FALSE or multiple est for(i in 1:2){ fun = switch(i, "1" = feols, "2" = feglm) res = feols(y ~ x_cst | fe1, base, warn = FALSE) res # => no error etable(res) # => no error # error when warn = TRUE test(feols(y ~ x_cst | fe1, base), "err") # multiple est => no error res = feols(c(y, x1) ~ x_cst | fe1, base) res # => no error etable(res) # => no error } # Removing the intercept!!! res = feols(y ~ -1 + x1 + i(fe1), base) test("(Intercept)" %in% names(res$coefficients), FALSE) res = feols(y ~ -1 + x1 + factor(fe1), base) test("(Intercept)" %in% names(res$coefficients), FALSE) res = feols(y ~ -1 + x1 + i(fe1) + i(fe2), base) test("(Intercept)" %in% names(res$coefficients), FALSE) test(is.null(res$collin.var), TRUE) # IV + interacted FEs res = feols(y ~ x1 | fe1^fe2 | x2 ~ x3, base) # IVs no exo var res = feols(y ~ 0 | x2 ~ x3, base) # Same in stepwise res = feols(y ~ 0 | sw0(fe1) | x2 ~ x3, base) # IVs + lags res = feols(y ~ x1 | fe1^fe2 | l(x2, -1:1) ~ l(x3, -1:1), base, panel.id = ~ fe1 + period) # functions in interactions res = feols(y ~ x1 | factor(fe1)^factor(fe2), base) res = feols(y ~ x1 | round(x2^2), base) test(feols(y ~ x1 | factor(fe1^fe2), base), "err") res = feols(y ~ x1 | bin(x2, "bin::1")^fe1 + fe1^fe2, base) #### #### ... Fit methods #### #### chunk("Fit methods") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$y_int = as.integer(base$y) base$y_log = sample(c(TRUE, FALSE), 150, TRUE) res = feglm.fit(base$y, base[, 2:4]) res_bis = feglm(y ~ -1 + x1 + x2 + x3, base) test(coef(res), coef(res_bis)) res = feglm.fit(base$y_int, base[, 2:4]) res_bis = feglm(y_int ~ -1 + x1 + x2 + x3, base) test(coef(res), coef(res_bis)) res = feglm.fit(base$y_log, base[, 2:4]) res_bis = feglm(y_log ~ -1 + x1 + x2 + x3, base) test(coef(res), coef(res_bis)) res = feglm.fit(base$y, base[, 2:4], family = "poisson") res_bis = feglm(y ~ -1 + x1 + x2 + x3, base, family = "poisson") test(coef(res), coef(res_bis)) res = feglm.fit(base$y_int, base[, 2:4], family = "poisson") res_bis = feglm(y_int ~ -1 + x1 + x2 + x3, base, family = "poisson") test(coef(res), coef(res_bis)) res = feglm.fit(base$y_log, base[, 2:4], family = "poisson") res_bis = feglm(y_log ~ -1 + x1 + x2 + x3, base, family = "poisson") test(coef(res), coef(res_bis)) #### #### ... Collinearity #### #### cat("COLLINEARITY\n\n") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$constant = 5 base$y_int = as.integer(base$y) base$w = as.vector(unclass(base$species) - 0.95) for(useWeights in c(FALSE, TRUE)){ for(model in c("ols", "pois")){ for(use_fe in c(FALSE, TRUE)){ cat(".") my_weight = NULL if(useWeights) my_weight = base$w adj = 1 if(model == "ols"){ if(!use_fe){ res = feols(y ~ x1 + constant, base, weights = my_weight) res_bis = lm(y ~ x1 + constant, base, weights = my_weight) } else { res = feols(y ~ x1 + constant | species, base, weights = my_weight) res_bis = lm(y ~ x1 + constant + species, base, weights = my_weight) } } else { if(!use_fe){ res = fepois(y_int ~ x1 + constant, base, weights = my_weight) res_bis = glm(y_int ~ x1 + constant, base, weights = my_weight, family = poisson) } else { res = fepois(y_int ~ x1 + constant | species, base, weights = my_weight) res_bis = glm(y_int ~ x1 + constant + species, base, weights = my_weight, family = poisson) } adj = 0 } test(coef(res)["x1"], coef(res_bis)["x1"], "~") test(se(res, se = "st", ssc = ssc(adj=adj))["x1"], se(res_bis)["x1"], "~") # cat("Weight: ", useWeights, ", model: ", model, ", FE: ", use_fe, "\n", sep="") } } } cat("\n") #### #### ... Non linear tests #### #### chunk("NON LINEAR") base = iris names(base) = c("y", "x1", "x2", "x3", "species") tab = c("versicolor" = 5, "setosa" = 0, "virginica" = -5) fun_nl = function(a, b, spec){ res = as.numeric(tab[spec]) a*res + b*res^2 } est_nl = feNmlm(y ~ x1, base, NL.fml = ~fun_nl(a, b, species), NL.start = 1, family = "gaussian") base$var_spec = as.numeric(tab[base$species]) est_lin = feols(y ~ x1 + var_spec + I(var_spec^2), base) test(coef(est_nl), coef(est_lin)[c(3, 4, 1, 2)], "~") #### #### ... Lagging #### #### # Different types of lag # 1) check no error in wide variety of situations # 2) check consistency chunk("LAGGING") data(base_did) base = base_did n = nrow(base) set.seed(0) base$y_na = base$y ; base$y_na[sample(n, 50)] = NA base$period_txt = letters[base$period] ten_dates = c("1960-01-15", "1960-01-16", "1960-03-31", "1960-04-05", "1960-05-12", "1960-05-25", "1960-06-20", "1960-07-30", "1965-01-02", "2002-12-05") base$period_date = as.Date(ten_dates, "%Y-%m-%d")[base$period] base$y_0 = base$y**2 ; base$y_0[base$id == 1] = 0 # We compute the lags "by hand" base = base[order(base$id, base$period), ] base$x1_lag = c(NA, base$x1[-n]) ; base$x1_lag[base$period == 1] = NA base$x1_lead = c(base$x1[-1], NA) ; base$x1_lead[base$period == 10] = NA base$x1_diff = base$x1 - base$x1_lag # we create holes base$period_bis = base$period ; base$period_bis[base$period_bis == 5] = 50 base$x1_lag_hole = base$x1_lag ; base$x1_lag_hole[base$period %in% c(5, 6)] = NA base$x1_lead_hole = base$x1_lead ; base$x1_lead_hole[base$period %in% c(4, 5)] = NA # we reshuffle the base base = base[sample(n), ] # # Checks consistency # cat("consistentcy...") test(lag(x1 ~ id + period, data = base), base$x1_lag) test(lag(x1 ~ id + period, -1, data = base), base$x1_lead) test(lag(x1 ~ id + period_bis, data = base), base$x1_lag_hole) test(lag(x1 ~ id + period_bis, -1, data = base), base$x1_lead_hole) test(lag(x1 ~ id + period_txt, data = base), base$x1_lag) test(lag(x1 ~ id + period_txt, -1, data = base), base$x1_lead) test(lag(x1 ~ id + period_date, data = base), base$x1_lag) test(lag(x1 ~ id + period_date, -1, data = base), base$x1_lead) cat("done.\nEstimations...") # # Estimations # # Poisson for(depvar in c("y", "y_na", "y_0")){ for(p in c("period", "period_txt", "period_date")){ base$per = base[[p]] cat(".") base$y_dep = base[[depvar]] pdat = panel(base, ~ id + period) if(depvar == "y_0"){ estfun = fepois } else { estfun = feols } est_raw = estfun(y_dep ~ x1 + x1_lag + x1_lead, base) est = estfun(y_dep ~ x1 + l(x1) + f(x1), base, panel.id = "id,per") est_pdat = estfun(y_dep ~ x1 + l(x1, 1) + f(x1, 1), pdat) test(coef(est_raw), coef(est)) test(coef(est_raw), coef(est_pdat)) # Now diff est_raw = estfun(y_dep ~ x1 + x1_diff, base) est = estfun(y_dep ~ x1 + d(x1), base, panel.id = "id,per") est_pdat = estfun(y_dep ~ x1 + d(x1, 1), pdat) test(coef(est_raw), coef(est)) test(coef(est_raw), coef(est_pdat)) # Now we just check that calls to l/f works without checking coefs est = estfun(y_dep ~ x1 + l(x1) + f(x1), base, panel.id = "id,per") est = estfun(y_dep ~ l(x1, -1:1) + f(x1, 2), base, panel.id = c("id", "per")) est = estfun(y_dep ~ l(x1, -1:1, fill = 1), base, panel.id = ~ id + per) if(depvar == "y") test(est$nobs, n) est = estfun(f(y_dep) ~ f(x1, -1:1), base, panel.id = ~ id + per) } } cat("done.\n\n") # # Data table # cat("data.table...") # We just check there is no bug (consistency should be OK) library(data.table) base_dt = data.table(id = c("A", "A", "B", "B"), time = c(1, 2, 1, 3), x = c(5, 6, 7, 8)) base_dt = panel(base_dt, ~id + time) base_dt[, x_l := l(x)] test(base_dt$x_l, c(NA, 5, NA, NA)) lag_creator = function(dt) { dt2 = panel(dt, ~id + time) dt2[, x_l := l(x)] return(dt2) } base_bis = lag_creator(base_dt) base_bis[, x_d := d(x)] cat("done.\n\n") # # Panel # # We ensure we get the right SEs whether we use the panel() or the panel.id method data(base_did) # Setting a data set as a panel... pdat = panel(base_did, ~id+period) pdat$fe = sample(15, nrow(pdat), replace = TRUE) base_panel = unpanel(pdat) est_pdat = feols(y ~ x1 | fe, pdat) est_panel = feols(y ~ x1 | fe, base_panel, panel.id = ~id+period) test(attr(vcov(est_pdat, attr = TRUE), "type"), attr(vcov(est_panel, attr = TRUE), "type")) #### #### ... subset #### #### chunk("SUBSET") set.seed(5) base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$fe_bis = sample(letters, 150, TRUE) base$x4 = rnorm(150) base$x1[sample(150, 5)] = NA fml = y ~ x1 + x2 # Errors test(feols(fml, base, subset = ~species), "err") test(feols(fml, base, subset = -1:15), "err") test(feols(fml, base, subset = integer(0)), "err") test(feols(fml, base, subset = c(TRUE, TRUE, FALSE)), "err") # Valid use for(id_fun in 1:6){ estfun = switch(as.character(id_fun), "1" = feols, "2" = feglm, "3" = fepois, "4" = femlm, "5" = fenegbin, "6" = feNmlm) for(id_fe in 1:5){ cat(".") fml = switch(as.character(id_fe), "1" = y ~ x1 + x2, "2" = y ~ x1 + x2 | species, "3" = y ~ x1 + x2 | fe_bis, "4" = y ~ x1 + x2 + i(fe_bis), "5" = y ~ x1 + x2 | fe_bis[x3]) if(id_fe == 5 && id_fun %in% 4:6) next if(id_fun == 6){ res_sub_a = estfun(fml, base, subset = ~species == "setosa", NL.fml = ~ a*x4, NL.start = 0) res_sub_b = estfun(fml, base, subset = base$species == "setosa", NL.fml = ~ a*x4, NL.start = 0) res_sub_c = estfun(fml, base, subset = which(base$species == "setosa"), NL.fml = ~ a*x4, NL.start = 0) res = estfun(fml, base[base$species == "setosa", ], NL.fml = ~ a*x4, NL.start = 0) } else { res_sub_a = estfun(fml, base, subset = ~species == "setosa") res_sub_b = estfun(fml, base, subset = base$species == "setosa") res_sub_c = estfun(fml, base, subset = which(base$species == "setosa")) res = estfun(fml, base[base$species == "setosa", ]) } test(coef(res_sub_a), coef(res)) test(coef(res_sub_b), coef(res)) test(coef(res_sub_c), coef(res)) test(se(res_sub_c, cluster = "fe_bis"), se(res, cluster = "fe_bis")) } cat("|") } cat("\n") #### #### ... split #### #### chunk("split") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) # simple: formula est = feols(y ~ x.[1:3], base, split = ~species %keep% "@^v") test(length(est), 2) est = feols(y ~ x.[1:3], base, fsplit = ~species %keep% c("set", "vers")) test(length(est), 3) est = feols(y ~ x.[1:3], base, split = ~species %drop% "set") test(length(est), 2) # simple: vector est = feols(y ~ x.[1:3], base, split = base$species %keep% "@^v") test(length(est), 2) est = feols(y ~ x.[1:3], base, split = base$species %keep% c("set", "vers")) test(length(est), 2) est = feols(y ~ x.[1:3], base, split = base$species %drop% "set") test(length(est), 2) # with bin est = feols(y ~ x.[1:2], base, split = ~bin(x3, c("cut::5", "saint emilion", "pessac leognan", "margaux", "saint julien", "entre deux mers")) %keep% c("saint e", "pe")) test(length(est), 2) est = feols(y ~ x.[1:2], base, split = ~bin(x3, c("cut::5", "saint emilion", "pessac leognan", NA)) %drop% "@\\d") test(length(est), 2) # with argument est = feols(y ~ x.[1:3], base, split = ~species, split.keep = "@^v") test(length(est), 2) est = feols(y ~ x.[1:3], base, fsplit = ~species, split.keep = c("set", "vers")) test(length(est), 3) est = feols(y ~ x.[1:3], base, split = ~species, split.drop = "set") test(length(est), 2) #### #### ... Multiple estimations #### #### chunk("Multiple") set.seed(2) base = iris names(base) = c("y1", "x1", "x2", "x3", "species") base$y2 = 10 + rnorm(150) + 0.5 * base$x1 base$x4 = rnorm(150) + 0.5 * base$y1 base$fe2 = rep(letters[1:15], 10) base$fe2[50:51] = NA base$y2[base$fe2 == "a" & !is.na(base$fe2)] = 0 base$x2[1:5] = NA base$x3[6] = NA base$x5 = rnorm(150) base$x6 = rnorm(150) + base$y1 * 0.25 base$fe3 = rep(letters[1:10], 15) for(id_fun in 1:5){ estfun = switch(as.character(id_fun), "1" = feols, "2" = feglm, "3" = fepois, "4" = femlm, "5" = feNmlm) # Following weird bug ASAN on CRAN I cannot replicate, check 4/5 not performed on non Windows if(Sys.info()["sysname"] != "Windows"){ if(id_fun %in% 4:5) next } est_multi = estfun(c(y1, y2) ~ x1 + sw(x2, x3), base, split = ~species) k = 1 for(s in c("setosa", "versicolor", "virginica")){ for(lhs in c("y1", "y2")){ for(rhs in c("x2", "x3")){ res = estfun(.[lhs] ~ x1 + .[rhs], base[base$species == s, ], notes = FALSE) test(coef(est_multi[[k]]), coef(res)) test(se(est_multi[[k]], cluster = "fe3"), se(res, cluster = "fe3")) k = k + 1 } } } cat("__") est_multi = estfun(c(y1, y2) ~ x1 + csw0(x2, x3) + x4 | species + fe2, base, fsplit = ~species) k = 1 all_rhs = c("", "x2", "x3") for(s in c("all", "setosa", "versicolor", "virginica")){ for(lhs in c("y1", "y2")){ for(n_rhs in 1:3){ if(s == "all"){ res = estfun(xpd(..lhs ~ x1 + ..rhs + x4 | species + fe2, ..lhs = lhs, ..rhs = all_rhs[1:n_rhs]), base, notes = FALSE) } else { res = estfun(xpd(..lhs ~ x1 + ..rhs + x4 | species + fe2, ..lhs = lhs, ..rhs = all_rhs[1:n_rhs]), base[base$species == s, ], notes = FALSE) } vname = names(coef(res)) test(coef(est_multi[[k]])[vname], coef(res), "~" , 1e-6) test(se(est_multi[[k]], cluster = "fe3")[vname], se(res, cluster = "fe3"), "~" , 1e-6) k = k + 1 } } } cat("|") } cat("\n") # No error tests # We test with IV + possible corner cases base$left = rnorm(150) base$right = rnorm(150) est_multi = feols(c(y1, y2) ~ sw0(x1) | sw0(species) | x2 ~ x3, base) # We check a few est_a = feols(y1 ~ 1 | x2 ~ x3, base) est_b = feols(y1 ~ x1 | species | x2 ~ x3, base) est_c = feols(y2 ~ 1 | x2 ~ x3, base) test(coef(est_multi[lhs = "y1", rhs = "^1", fixef = "1", drop = TRUE]), coef(est_a)) test(coef(est_multi[lhs = "y1", rhs = "x1", fixef = "spe", drop = TRUE]), coef(est_b)) test(coef(est_multi[lhs = "y2", rhs = "^1", fixef = "1", drop = TRUE]), coef(est_c)) # with fixed covariates est_multi_LR = feols(c(y1, y2) ~ left + sw0(x1*x4) + right | sw0(species) | x2 ~ x3, base) est_a = feols(y1 ~ left + right | x2 ~ x3, base) est_b = feols(y1 ~ left + x1*x4 + right | species | x2 ~ x3, base) est_c = feols(y2 ~ left + right | x2 ~ x3, base) test(coef(est_multi_LR[lhs = "y1", rhs = "!x1", fixef = "1", drop = TRUE]), coef(est_a)) user_name = c("fit_x2", "left", "x1", "x4", "x1:x4", "right") test(names(coef(est_multi_LR[lhs = "y1", rhs = "x1", fixef = "spe", drop = TRUE])), user_name) test(coef(est_multi_LR[lhs = "y1", rhs = "x1", fixef = "spe", drop = TRUE]), coef(est_b)[user_name]) test(coef(est_multi_LR[lhs = "y2", rhs = "!x1", fixef = "1", drop = TRUE]), coef(est_c)) # mvsw est_mvsw = feols(y1 ~ mvsw(x1, x2), base) est_mvsw_fe = feols(y1 ~ mvsw(x1, x2) | mvsw(species, fe2), base) est_mvsw_fe_iv = feols(y1 ~ mvsw(x1, x2) | mvsw(species, fe2) | x3 ~ x4, base) test(length(est_mvsw), 4) test(length(as.list(est_mvsw_fe)), 16) test(length(as.list(est_mvsw_fe_iv)), 16) # Summary of multiple endo vars est_multi_iv = feols(c(y1, y2) ~ sw0(x1) | sw0(species) | x3 + x4 ~ x5 + x6, base) test(length(est_multi_iv), 8) test(length(summary(est_multi_iv, stage = 1)), 16) # IV without exo var: est_mult_no_exo = feols(c(y1, y2) ~ 0 | x3 + x4 ~ x5 + x6, base) est_no_exo_y2 = feols(y2 ~ 0 | x3 + x4 ~ x5 + x6, base) test(coef(est_mult_no_exo[[2]]), coef(est_no_exo_y2)) # proper ordering est_multi = feols(c(y1, y2) ~ sw0(x1) | sw0(fe2), base, split = ~species) test(names(models(est_multi[fixef = TRUE, sample = FALSE])), dsb("/id, fixef, lhs, rhs, sample.var, sample")) test(names(models(est_multi[fixef = "fe2", sample = "seto"])), dsb("/id, fixef, sample.var, sample, lhs, rhs")) test(names(models(est_multi[fixef = "fe2", sample = "seto", reorder = FALSE])), dsb("/id, sample.var, sample, fixef, lhs, rhs")) # NA models base$y_0 = base$x1 ** 2 + rnorm(150) base$y_0[base$species == "setosa"] = 0 est_pois = fepois(y_0 ~ csw(x.[,1:4]), base, split = ~species) base$x1_bis = base$x1 est_pois = fepois(y_0 ~ x.[1:3] + x1_bis | sw0(species), base) # Different ways .[] base = setNames(iris, c("y", "x1", "x2", "x3", "species")) dep_all = list(dsb("/y, x1, x2"), ~y + x1 + x2) for(dep in dep_all){ m = feols(.[dep] ~ x3, base) test(length(m), 3) m = feols(x3 ~ .[dep], base) test(length(m$coefficients), 4) m = feols(x3 ~ csw(.[,dep]), base) test(length(m), 3) } #### #### ... IV #### #### chunk("IV") base = iris names(base) = c("y", "x1", "x_endo_1", "x_inst_1", "fe") set.seed(2) base$x_inst_2 = 0.2 * base$y + 0.2 * base$x_endo_1 + rnorm(150, sd = 0.5) base$x_endo_2 = 0.2 * base$y - 0.2 * base$x_inst_1 + rnorm(150, sd = 0.5) # Checking a basic estimation setFixest_vcov(all = "iid") est_iv = feols(y ~ x1 | x_endo_1 + x_endo_2 ~ x_inst_1 + x_inst_2, base) res_f1 = feols(x_endo_1 ~ x1 + x_inst_1 + x_inst_2, base) res_f2 = feols(x_endo_2 ~ x1 + x_inst_1 + x_inst_2, base) base$fit_x_endo_1 = predict(res_f1) base$fit_x_endo_2 = predict(res_f2) res_2nd = feols(y ~ fit_x_endo_1 + fit_x_endo_2 + x1, base) # the coef test(coef(est_iv), coef(res_2nd)) # the SE resid_iv = base$y - predict(res_2nd, data.frame(x1 = base$x1, fit_x_endo_1 = base$x_endo_1, fit_x_endo_2 = base$x_endo_2)) sigma2_iv = sum(resid_iv**2) / (res_2nd$nobs - res_2nd$nparams) sum_2nd = summary(res_2nd, .vcov = res_2nd$cov.iid / res_2nd$sigma2 * sigma2_iv) # We only check that on Windows => avoids super odd bug in fedora devel # The worst is that I just can't debug it.... so that's the way it's done. if(Sys.info()["sysname"] == "Windows"){ test(se(sum_2nd), se(est_iv)) } # check no bug etable(summary(est_iv, stage = 1:2)) setFixest_vcov(reset = TRUE) #### #### ... VCOV at estimation #### #### chunk("vcov at estimation") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$clu = sample(6, 150, TRUE) base$clu[1:5] = NA est = feols(y ~ x1 | species, base, cluster = ~clu, ssc = ssc(adj = FALSE)) # The three should be identical v1 = est$cov.scaled v1b = vcov(est) v1c = summary(est)$cov.scaled test(v1, v1b) test(v1, v1c) # Only ssc change v2 = summary(est, ssc = ssc())$cov.scaled v2b = vcov(est, cluster = ~clu, ssc = ssc()) test(v2, v2b) test(max(abs(v1 - v2)) == 0, FALSE) # SE change only v3 = summary(est, se = "hetero")$cov.scaled v3b = vcov(est, se = "hetero", ssc = ssc(adj = FALSE)) test(v3, v3b) test(max(abs(v1 - v3)) == 0, FALSE) test(max(abs(v2 - v3)) == 0, FALSE) # feols.fit ymat = base$y xmat = base[, 2:3] fe = base$species for(use_fe in c(TRUE, FALSE)){ all_vcov = dsb("/iid, hetero") if(use_fe){ setFixest_fml(..fe = ~ 1 | species) all_vcov = c(all_vcov, "cluster") } else { setFixest_fml(..fe = ~ 1) } for(v in all_vcov){ if(use_fe){ est_fit = feols.fit(ymat, xmat, fe, vcov = v) } else { est_fit = feols.fit(ymat, cbind(1, xmat), vcov = v) } est = feols(y ~ x1 + x2 + ..fe, base, vcov = v) test(vcov(est), vcov(est_fit)) } } #### #### ... Argument sliding #### #### chunk("argument sliding") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) setFixest_estimation(data = base) raw = feols(y ~ x1 + x2, base, ~species) slided = feols(y ~ x1 + x2, ~species) test(coef(raw), coef(slided)) # Error, with error msg relative to 'data' test(feols(y ~ x1 + x2, 1:5), "err") # should be another estimation other_est = feols(y ~ x1 + x2, head(base, 50)) test(nobs(other_est), 50) setFixest_estimation(reset = TRUE) #### #### ... Offset #### #### chunk("offset") # we test the different ways to set an offset base = setNames(iris, c("y", "x1", "x2", "x3", "species")) o1 = feols(y ~ x1 + offset(x2) + offset(x3^2 + 3), base) o2 = feols(y ~ x1, base, offset = ~x2 + x3^2 + 3) test(coef(o1), coef(o2)) # error test(feols(y ~ x1 + offset(x2), base, offset = ~x3), "err") #### #### ... Only Coef #### #### chunk("only.coef") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) base$x4 = base$x1 + 5 m = feols(y ~ x1 + x2 + x4, base, only.coef = TRUE) test(length(m), 4) test(sum(is.na(m)), 1) m = fepois(y ~ x1 + x2 + x4, base, only.coef = TRUE) test(length(m), 4) test(sum(is.na(m)), 1) m = femlm(y ~ x1 + x2, base, only.coef = TRUE) test(length(m), 3) test(sum(is.na(m)), 0) test(feols(y ~ sw(x1, x2), base, only.coef = TRUE), "err") #### #### Standard-errors #### #### chunk("STANDARD ERRORS") # # Fixed-effects corrections # # We create "irregular" FEs set.seed(0) base = data.frame(x = rnorm(20)) base$y = base$x + rnorm(20) base$fe1 = rep(rep(1:3, c(4, 3, 3)), 2) base$fe2 = rep(rep(1:5, each = 2), 2) est = feols(y ~ x | fe1 + fe2, base) # fe1: 3 FEs # fe2: 5 FEs # # Clustered standard-errors: by fe1 # # Default: fixef.K = "nested" # => adjustment K = 1 + 5 (i.e. x + fe2) test(attr(vcov(est, ssc = ssc(fixef.K = "nested"), attr = TRUE), "dof.K"), 6) # fixef.K = FALSE # => adjustment K = 1 (i.e. only x) test(attr(vcov(est, ssc = ssc(fixef.K = "none"), attr = TRUE), "dof.K"), 1) # fixef.K = TRUE # => adjustment K = 1 + 3 + 5 - 1 (i.e. x + fe1 + fe2 - 1 restriction) test(attr(vcov(est, ssc = ssc(fixef.K = "full"), attr = TRUE), "dof.K"), 8) # fixef.K = TRUE & fixef.exact = TRUE # => adjustment K = 1 + 3 + 5 - 2 (i.e. x + fe1 + fe2 - 2 restrictions) test(attr(vcov(est, ssc = ssc(fixef.K = "full", fixef.force_exact = TRUE), attr = TRUE), "dof.K"), 7) # # Manual checks of the SEs # n = est$nobs VCOV_raw = est$cov.iid / ((n - 1) / (n - est$nparams)) # standard for(k_val in c("none", "nested", "full")){ for(adj in c(FALSE, TRUE)){ K = switch(k_val, none = 1, nested = 8, full = 8) my_adj = ifelse(adj, (n - 1) / (n - K), 1) test(vcov(est, se = "standard", ssc = ssc(adj = adj, fixef.K = k_val)), VCOV_raw * my_adj) # cat("adj = ", adj, " ; fixef.K = ", k_val, "\n", sep = "") } } # Clustered, fe1 VCOV_raw = est$cov.iid / est$sigma2 H = vcovClust(est$fixef_id$fe1, VCOV_raw, scores = est$scores, adj = FALSE) n = nobs(est) for(tdf in c("conventional", "min")){ for(k_val in c("none", "nested", "full")){ for(c_adj in c(FALSE, TRUE)){ for(adj in c(FALSE, TRUE)){ K = switch(k_val, none = 1, nested = 6, full = 8) cluster_factor = ifelse(c_adj, 3/2, 1) df = ifelse(tdf == "min", 2, 20 - K) my_adj = ifelse(adj, (n - 1) / (n - K), 1) V = H * cluster_factor # test SE test(vcov(est, se = "cluster", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj)), V * my_adj) # test pvalue my_tstat = tstat(est, se = "cluster", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj)) test(pvalue(est, se = "cluster", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj, t.df = tdf)), 2*pt(-abs(my_tstat), df)) # cat("adj = ", adj, " ; fixef.K = ", k_val, " ; cluster.adj = ", c_adj, " t.df = ", tdf, "\n", sep = "") } } } } # 2-way Clustered, fe1 fe2 VCOV_raw = est$cov.iid / est$sigma2 M_i = vcovClust(est$fixef_id$fe1, VCOV_raw, scores = est$scores, adj = FALSE) M_t = vcovClust(est$fixef_id$fe2, VCOV_raw, scores = est$scores, adj = FALSE) M_it = vcovClust(paste(base$fe1, base$fe2), VCOV_raw, scores = est$scores, adj = FALSE, do.unclass = TRUE) M_i + M_t - M_it vcov(est, se = "two", ssc = ssc(adj = FALSE, cluster.adj = FALSE)) for(cdf in c("conventional", "min")){ for(tdf in c("conventional", "min")){ for(k_val in c("none", "nested", "full")){ for(c_adj in c(FALSE, TRUE)){ for(adj in c(FALSE, TRUE)){ K = switch(k_val, none = 1, nested = 2, full = 8) if(c_adj){ if(cdf == "min"){ V = (M_i + M_t - M_it) * 3/2 } else { V = M_i * 3/2 + M_t * 5/4 - M_it * 6/5 } } else { V = M_i + M_t - M_it } df = ifelse(tdf == "min", 2, 20 - K) my_adj = ifelse(adj, (n - 1) / (n - K), 1) # test SE test(vcov(est, se = "two", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj, cluster.df = cdf)), V * my_adj) # test pvalue my_tstat = tstat(est, se = "two", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj, cluster.df = cdf)) test(pvalue(est, se = "two", ssc = ssc(adj = adj, fixef.K = k_val, cluster.adj = c_adj, cluster.df = cdf, t.df = tdf)), 2*pt(-abs(my_tstat), df)) # cat("adj = ", adj, " ; fixef.K = ", k_val, " ; cluster.adj = ", c_adj, " t.df = ", tdf, "\n", sep = "") } } } } } # # Comparison with sandwich and plm # library(sandwich) # Data generation set.seed(0) N = 20; G = N/5; T = N/G d = data.frame( y=rnorm(N), x=rnorm(N), grp=rep(1:G,T), tm=rep(1:T,each=G) ) # Estimations est_lm = lm(y ~ x + as.factor(grp) + as.factor(tm), data=d) est_feols = feols(y ~ x | grp + tm, data=d) # # Standard # test(se(est_feols, se = "st")["x"], se(est_lm)["x"]) # # Clustered # # Clustered by grp se_CL_grp_lm_HC1 = sqrt(vcovCL(est_lm, cluster = d$grp, type = "HC1")["x", "x"]) se_CL_grp_lm_HC0 = sqrt(vcovCL(est_lm, cluster = d$grp, type = "HC0")["x", "x"]) # How to get the lm test(se(est_feols, ssc = ssc(fixef.K = "full")), se_CL_grp_lm_HC1) test(se(est_feols, ssc = ssc(adj = FALSE, fixef.K = "full")), se_CL_grp_lm_HC0) # # Heteroskedasticity-robust # se_white_lm_HC1 = sqrt(vcovHC(est_lm, type = "HC1")["x", "x"]) se_white_lm_HC0 = sqrt(vcovHC(est_lm, type = "HC0")["x", "x"]) test(se(est_feols, se = "hetero"), se_white_lm_HC1) test(se(est_feols, se = "hetero", ssc = ssc(adj = FALSE, cluster.adj = FALSE)), se_white_lm_HC0) # # Two way # # Clustered by grp & tm se_CL_2w_lm = sqrt(vcovCL(est_lm, cluster = ~ grp + tm, type = "HC1")["x", "x"]) se_CL_2w_feols = se(est_feols, se = "twoway") test(se(est_feols, se = "twoway", ssc = ssc(fixef.K = "full", cluster.df = "conv")), se_CL_2w_lm) # # Checking the calls work properly # data(trade) est_pois = femlm(Euros ~ log(dist_km)|Origin+Destination, trade) se_clust = se(est_pois, se = "cluster", cluster = "Product") test(se(est_pois, cluster = trade$Product), se_clust) test(se(est_pois, cluster = ~Product), se_clust) se_two = se(est_pois, se = "twoway", cluster = trade[, c("Product", "Destination")]) test(se_two, se(est_pois, cluster = c("Product", "Destination"))) test(se_two, se(est_pois, cluster = ~Product+Destination)) se_clu_comb = se(est_pois, cluster = "Product^Destination") test(se_clu_comb, se(est_pois, cluster = paste(trade$Product, trade$Destination))) test(se_clu_comb, se(est_pois, cluster = ~Product^Destination)) se_two_comb = se(est_pois, cluster = c("Origin^Destination", "Product")) test(se_two_comb, se(est_pois, cluster = list(paste(trade$Origin, trade$Destination), trade$Product))) test(se_two_comb, se(est_pois, cluster = ~Origin^Destination + Product)) # With cluster removed base = trade base$Euros[base$Origin == "FR"] = 0 est_pois = femlm(Euros ~ log(dist_km)|Origin+Destination, base) se_clust = se(est_pois, se = "cluster", cluster = "Product") test(se(est_pois, cluster = base$Product), se_clust) test(se(est_pois, cluster = ~Product), se_clust) se_two = se(est_pois, se = "twoway", cluster = base[, c("Product", "Destination")]) test(se_two, se(est_pois, cluster = c("Product", "Destination"))) test(se_two, se(est_pois, cluster = ~Product+Destination)) se_clu_comb = se(est_pois, cluster = "Product^Destination") test(se_clu_comb, se(est_pois, cluster = paste(base$Product, base$Destination))) test(se_clu_comb, se(est_pois, cluster = ~Product^Destination)) se_two_comb = se(est_pois, cluster = c("Origin^Destination", "Product")) test(se_two_comb, se(est_pois, cluster = list(paste(base$Origin, base$Destination), base$Product))) test(se_two_comb, se(est_pois, cluster = ~Origin^Destination + Product)) # With cluster removed and NAs base = trade base$Euros[base$Origin == "FR"] = 0 base$Euros_na = base$Euros ; base$Euros_na[sample(nrow(base), 50)] = NA base$Destination_na = base$Destination ; base$Destination_na[sample(nrow(base), 50)] = NA base$Origin_na = base$Origin ; base$Origin_na[sample(nrow(base), 50)] = NA base$Product_na = base$Product ; base$Product_na[sample(nrow(base), 50)] = NA est_pois = femlm(Euros ~ log(dist_km)|Origin+Destination_na, base) se_clust = se(est_pois, se = "cluster", cluster = "Product") test(se(est_pois, cluster = base$Product), se_clust) test(se(est_pois, cluster = ~Product), se_clust) se_two = se(est_pois, se = "twoway", cluster = base[, c("Product", "Destination")]) test(se_two, se(est_pois, cluster = c("Product", "Destination"))) test(se_two, se(est_pois, cluster = ~Product+Destination)) se_clu_comb = se(est_pois, cluster = "Product^Destination") test(se_clu_comb, se(est_pois, cluster = paste(base$Product, base$Destination))) test(se_clu_comb, se(est_pois, cluster = ~Product^Destination)) se_two_comb = se(est_pois, cluster = c("Origin^Destination", "Product")) test(se_two_comb, se(est_pois, cluster = list(paste(base$Origin, base$Destination), base$Product))) test(se_two_comb, se(est_pois, cluster = ~Origin^Destination + Product)) # # Checking errors # # Should report error test(se(est_pois, cluster = "Origin_na"), "err") test(se(est_pois, cluster = base$Origin_na), "err") test(se(est_pois, cluster = list(base$Origin_na)), "err") test(se(est_pois, cluster = ~Origin_na^Destination), "err") test(se(est_pois, se = "cluster", cluster = ~Origin_na^not_there), "err") # # Checking that the aliases work fine # se_hetero = se(est_pois, se = "hetero") se_hc1 = se(est_pois, se = "hc1") se_white = se(est_pois, se = "white") test(se_hetero, se_hc1) test(se_hetero, se_white) # # New argument vcov # # We mostly check the absence of errors data(base_did) est_panel = feols(y ~ x1, base_did, panel.id = ~id + period, subset = 1:500) se_est = se(est_panel) test(se(est_panel, ~id), se_est) # changing ssc argument test(se(est_panel, ssc = ssc(adj = FALSE)), se(est_panel, ~id + ssc(adj = FALSE))) # using vcov_cluster test(se_est, se(est_panel, vcov_cluster("id"))) test(se_est, se(vcov_cluster(est_panel, "id"))) # NW se_NW = se(est_panel, "NW") test(se_NW, se(est_panel, NW ~ id + period)) test(se_NW, se(est_panel, newey ~ id + period)) test(se_NW, se(est_panel, vcov_NW("id", "period"))) test(se_NW, se(est_panel, vcov_NW(time = "period"))) # here unit is deduced se_NW2 = se(est_panel, NW(2)) test(se_NW2, se(est_panel, NW(2) ~ id + period)) test(se_NW2, se(est_panel, vcov_NW(lag = 2))) # errors est = feols(y ~ x1, base_did) test(se(est, NW ~ period), "err") # DK se_DK = se(est_panel, "DK") test(se_DK, se(est_panel, DK ~ period)) test(se_DK, se(est_panel, dris ~ period)) test(se_DK, se(est_panel, vcov_DK("period"))) se_DK2 = se(est_panel, DK(2)) test(se_DK2, se(est_panel, DK(2) ~ period)) test(se_DK2, se(est_panel, vcov_DK(lag = 2))) # Conley data(quakes) est = feols(depth ~ mag, quakes, "conley") se_conley = se(est) test(se_conley, se(est, conley(90) ~ 1)) test(se_conley, se(est, conley(90) ~ lat + long)) se_conley200 = se(est, conley(200) ~ lat + long) test(se_conley200, se(est, vcov_conley(cutoff = 200))) test(se_conley200, se(est, vcov_conley("lat", "long", cutoff = 200))) se_conleyExtra = se(est, conley(pixel = 20, distance = "spherical")) test(se_conleyExtra, se(vcov_conley(est, pixel = 20, distance = "spherical"))) # Checking the value of Conley SEs with equivalences # we generate data that leads to simple values base = iris names(base) = c("y", "x1", "x2", "x3", "species") # scattered along 111km base$lat = rep(seq(-0.5, 0.5, length.out = 50), 3) # scattered across very long distances base$lon = rep(c(0, 80, 160), each = 50) est = feols(y ~ x1, base) # Equivalence 1 -- clustered SEs se_clu = se(est, ~lon + ssc(adj = FALSE, cluster.adj = FALSE)) test(se_clu, se(est, conley(200) ~ ssc(adj = FALSE))) # Equivalence 2 -- White SEs se_hc1 = se(est, hetero ~ ssc(adj = FALSE, cluster.adj = FALSE)) test(se_hc1, se(est, conley(1) ~ ssc(adj = FALSE))) # # ssc with custom t.df values # est = feols(y ~ x1 + x2, base) m = summary(est, ssc = ssc(t.df = 5)) test(m$coeftable[, 4], 2*pt(-abs(m$coeftable[, 3]), 5)) # # feols.fit # base = setNames(iris, c("y", "x1", "x2", "x3", "species")) est = feols(y ~ x1 | species, base, vcov = "hete") est_fit = feols.fit(base$y, base$x1, base$species, vcov = "hete") test(se(est), se(est_fit)) est = feols(y ~ x1 | species, base, cluster = base$species) est_fit = feols.fit(base$y, base$x1, base$species, cluster = base$species) test(se(est), se(est_fit)) est = feols(y ~ x1 | species, base, vcov = "cluster") est_fit = feols.fit(base$y, base$x1, base$species, vcov = "cluster") test(se(est), se(est_fit)) # error for the other VCOVs test(feols.fit(base$y, base$x1, base$species, vcov = "hac"), "err") test(feols.fit(base$y, base$x1, base$species, vcov = "conley"), "err") #### #### Residuals #### #### chunk("RESIDUALS") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$y_int = as.integer(base$y) + 1 # OLS + GLM + FENMLM for(method in c("ols", "feglm", "femlm", "fenegbin")){ cat("Method: ", format(method, width = 8)) for(do_weight in c(FALSE, TRUE)){ cat(".") if(do_weight){ w = unclass(as.factor(base$species)) } else { w = NULL } if(method == "ols"){ m = feols(y_int ~ x1 | species, base, weights = w) mm = lm(y_int ~ x1 + species, base, weights = w) } else if(method == "feglm"){ m = feglm(y_int ~ x1 | species, base, weights = w, family = "poisson") mm = glm(y_int ~ x1 + species, base, weights = w, family = poisson()) } else if(method == "femlm"){ if(!is.null(w)) next m = femlm(y_int ~ x1 | species, base) mm = glm(y_int ~ x1 + species, base, family = poisson()) } else if(method == "fenegbin"){ if(!is.null(w)) next m = fenegbin(y_int ~ x1 | species, base, notes = FALSE) mm = MASS::glm.nb(y_int ~ x1 + species, base) } tol = ifelse(method == "fenegbin", 1e-2, 1e-6) test(resid(m, "r"), resid(mm, "resp"), "~", tol = tol) test(resid(m, "d"), resid(mm, "d"), "~", tol = tol) test(resid(m, "p"), resid(mm, "pearson"), "~", tol = tol) test(deviance(m), deviance(mm), "~", tol = tol) } cat("\n") } cat("\n") #### #### fixef #### #### chunk("FIXEF") set.seed(0) base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$x4 = rnorm(150) + 0.25*base$y base$fe_bis = sample(10, 150, TRUE) base$fe_ter = sample(15, 150, TRUE) get_coef = function(all_coef, x){ res = all_coef[grepl(x, names(all_coef), perl = TRUE)] names(res) = gsub(x, "", names(res), perl = TRUE) res } # # With 2 x 1 FE # m = feols(y ~ x1 + x2 | species + fe_bis, base) all_coef = coef(feols(y ~ -1 + x1 + x2 + species + factor(fe_bis), base)) m_fe = fixef(m) c1 = get_coef(all_coef, "species") test(var(c1 - m_fe$species[names(c1)]), 0) c2 = get_coef(all_coef, "factor\\(fe_bis\\)") test(var(c2 - m_fe$fe_bis[names(c2)]), 0) # # With 1 FE + 1 FE 1 VS # m = feols(y ~ x1 + x2 | species + fe_bis[x3], base) all_coef = coef(feols(y ~ -1 + x1 + x2 + species + factor(fe_bis) + i(fe_bis, x3), base)) m_fe = fixef(m) c1 = get_coef(all_coef, "species") test(var(c1 - m_fe$species[names(c1)]), 0, "~") c2 = get_coef(all_coef, "factor\\(fe_bis\\)") test(var(c2 - m_fe$fe_bis[names(c2)]), 0, "~") c3 = get_coef(all_coef, "fe_bis::|:x3") test(c3, m_fe[["fe_bis[[x3]]"]][names(c3)], "~", tol = 1e-5) # # With 2 x (1 FE + 1 VS) + 1 FE # m = feols(y ~ x1 | species[x2] + fe_bis[x3] + fe_ter, base) all_coef = coef(feols(y ~ -1 + x1 + species + i(species, x2) + factor(fe_bis) + i(fe_bis, x3) + factor(fe_ter), base)) m_fe = fixef(m) c1 = get_coef(all_coef, "^species(?=[^:])") test(var(c1 - m_fe$species[names(c1)]), 0, "~") c2 = get_coef(all_coef, "^factor\\(fe_bis\\)") test(var(c2 - m_fe$fe_bis[names(c2)]), 0, "~") c3 = get_coef(all_coef, "fe_bis::|:x3") test(c3, m_fe[["fe_bis[[x3]]"]][names(c3)], "~", tol = 2e-4) c4 = get_coef(all_coef, "species::|:x2") test(c4, m_fe[["species[[x2]]"]][names(c4)], "~", tol = 2e-4) # # With 2 x (1 FE) + 1 FE 2 VS # m = feols(y ~ x1 | species + fe_bis[x2,x3] + fe_ter, base) all_coef = coef(feols(y ~ x1 + species + factor(fe_bis) + i(fe_bis, x2) + i(fe_bis, x3) + factor(fe_ter), base)) m_fe = fixef(m) c1 = get_coef(all_coef, "^species") test(var(c1 - m_fe$species[names(c1)]), 0, "~") c2 = get_coef(all_coef, "^factor\\(fe_bis\\)") test(var(c2 - m_fe$fe_bis[names(c2)]), 0, "~") c3 = get_coef(all_coef, "fe_bis::(?=.+x2)|:x2") test(c3, m_fe[["fe_bis[[x2]]"]][names(c3)], "~", tol = 2e-4) c4 = get_coef(all_coef, "fe_bis::(?=.+x3)|:x3") test(c4, m_fe[["fe_bis[[x3]]"]][names(c4)], "~", tol = 2e-4) # # With weights # w = 3 * (as.integer(base$species) - 0.95) m = feols(y ~ x1 | species + fe_bis[x2,x3] + fe_ter, base, weights = w) all_coef = coef(feols(y ~ x1 + species + factor(fe_bis) + i(fe_bis, x2) + i(fe_bis, x3) + factor(fe_ter), base, weights = w)) m_fe = fixef(m) c1 = get_coef(all_coef, "^species") test(var(c1 - m_fe$species[names(c1)]), 0, "~") c2 = get_coef(all_coef, "^factor\\(fe_bis\\)") test(var(c2 - m_fe$fe_bis[names(c2)]), 0, "~") c3 = get_coef(all_coef, "fe_bis::(?=.+x2)|:x2") test(c3, m_fe[["fe_bis[[x2]]"]][names(c3)], "~", tol = 2e-4) c4 = get_coef(all_coef, "fe_bis::(?=.+x3)|:x3") test(c4, m_fe[["fe_bis[[x3]]"]][names(c4)], "~", tol = 2e-4) #### #### To Integer #### #### chunk("TO_INTEGER") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$z = sample(5, 150, TRUE) # Normal m = to_integer(base$species) test(length(unique(m)), 3) m = to_integer(base$species, base$z) test(length(unique(m)), 15) # with NA base$species_na = base$species base$species_na[base$species == "setosa"] = NA m = to_integer(base$species_na, base$z) test(length(unique(m)), 11) m = to_integer(base$species_na, base$z, add_items = TRUE, items.list = TRUE) test(length(m$items), 10) #### #### Interact #### #### chunk("Interact") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) base$fe_2 = round(seq(-5, 5, length.out = 150)) # # We just ensure it works without error # m = feols(y ~ x1 + i(fe_2), base) coefplot(m) etable(m, dict = c("0" = "zero")) m = feols(y ~ x1 + i(fe_2) + i(fe_2, x2), base) coefplot(m) etable(m, dict = c("0" = "zero")) a = i(base$fe_2) b = i(base$fe_2, ref = 0:1) d = i(base$fe_2, keep = 0:1) test(ncol(a), ncol(b) + 2) test(ncol(d), 2) # # binning # m = feols(y ~ x1 + i(fe_2, bin = list("0" = -1:1)), base) test(length(coef(m)), 12 - 2) # SA data(base_stagg) res_sunab = feols(y ~ x1 + sunab(year_treated, year, bin = "bin::2"), base_stagg) iplot(res_sunab) test(length(coef(res_sunab)), 15) res_sunab = feols(y ~ x1 + sunab(year_treated, year, bin.rel = "bin::2"), base_stagg) iplot(res_sunab) test(length(coef(res_sunab)), 12) #### #### bin #### #### chunk("BIN") plen = iris$Petal.Length years = round(rnorm(1000, 2000, 5)) my_cuts = c("cut::3", "cut::2]5]", "cut::q1]q2]q3]", "cut::p20]p50]p70]p90]", "cut::2[q2]p90]") for(type in 1:2){ x = switch(type, "1" = plen, "2" = years) for(cut in my_cuts){ my_bin = bin(x, cut) bin_char = as.character(my_bin) if(grepl("[", bin_char[1], fixed = TRUE)){ all_min = as.numeric(gsub("(^\\[)|(;.+)", "", bin_char)) all_max = as.numeric(gsub(".+; |\\]", "", bin_char)) } else { all_min = as.numeric(gsub("-.+", "", bin_char)) all_max = as.numeric(gsub(".+-", "", bin_char)) } test(all(x >= all_min), TRUE) test(all(x <= all_max), TRUE) } } #### #### demean #### #### chunk("DEMEAN") data(trade) base = trade base$ln_euros = log(base$Euros) base$ln_dist = log(base$dist_km) X = base[, c("ln_euros", "ln_dist")] fe = base[, c("Origin", "Destination")] base_new = demean(X, fe) a = feols(ln_euros ~ ln_dist, base_new) b = feols(ln_euros ~ ln_dist | Origin + Destination, base, demeaned = TRUE) test(coef(a)[-1], coef(b), "~", 1e-12) test(base_new$ln_euros, b$y_demeaned) test(base_new$ln_dist, b$X_demeaned) # Now we just check there's no error # NAs X_NA = X fe_NA = fe X_NA[1:5, 1] = NA fe_NA[6:10, 1] = NA X_demean = demean(X_NA, fe_NA, na.rm = FALSE) test(nrow(X_demean), nrow(X)) # integer X_int = X X_int[[1]] = as.integer(X_int[[1]]) X_demean = demean(X_int, fe) # matrix/DF X_demean = demean(X_int, fe, as.matrix = TRUE) test(is.matrix(X_demean), TRUE) X_demean = demean(as.matrix(X_int), fe, as.matrix = FALSE) test(!is.matrix(X_demean), TRUE) # fml X_demean = demean(ln_dist ~ Origin + Destination, data = base) # slopes X_dm_slopes = demean(ln_dist ~ Origin + Destination[ln_euros], data = base) X_dm_slopes_bis = demean(base$ln_dist, fe, slope.vars = base$ln_euros, slope.flag = c(0, 1)) test(X_dm_slopes[[1]], X_dm_slopes_bis) #### #### hatvalues #### #### chunk("HATVALUES") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) base$y_int = as.integer(base$y) base$y_bin = 1 * (base$y > mean(base$y)) fm = lm(y ~ x1 + x2, base) ffm = feols(y ~ x1 + x2, base) test(hatvalues(ffm), hatvalues(fm)) glm_poi = glm(y_int ~ x1 + x2, family = poisson(), base) feglm_poi = fepois(y_int ~ x1 + x2, base) test(hatvalues(feglm_poi), hatvalues(glm_poi)) glm_logit = glm(y_bin ~ x1 + x2, family = binomial(), base) feglm_logit = feglm(y_bin ~ x1 + x2, base, binomial()) test(hatvalues(feglm_logit), hatvalues(glm_logit)) glm_probit = glm(y_bin ~ x1 + x2, family = binomial("probit"), base) feglm_probit = feglm(y_bin ~ x1 + x2, base, binomial("probit")) test(hatvalues(feglm_probit), hatvalues(glm_probit)) #### #### sandwich #### #### chunk("SANDWICH") # Compatibility with sandwich library(sandwich) data(base_did) est = feols(y ~ x1 + I(x1**2) + factor(id), base_did) test(vcov(est, cluster = ~id), vcovCL(est, cluster = ~id, type = "HC1")) est_pois = fepois(as.integer(y) + 20 ~ x1 + I(x1**2) + factor(id), base_did) test(vcov(est_pois, cluster = ~id), vcovCL(est_pois, cluster = ~id, type = "HC1")) # With FEs est = feols(y ~ x1 + I(x1**2) | id, base_did) test(vcov(est, cluster = ~id, ssc = ssc(adj = FALSE)), vcovCL(est, cluster = ~id)) est_pois = fepois(as.integer(y) + 20 ~ x1 + I(x1**2) | id, base_did) test(vcov(est_pois, cluster = ~id, ssc = ssc(adj = FALSE)), vcovCL(est_pois, cluster = ~id)) #### #### only.env #### #### # We check that there's no problem when using the environment chunk("ONLY ENV") base = iris names(base) = c("y", "x1", "x2", "x3", "species") env = feols(y ~ x1 + x2 | species, base, only.env = TRUE) feols(env = env) env = feglm(y ~ x1 + x2 | species, base, only.env = TRUE) feglm(env = env) env = fepois(y ~ x1 + x2 | species, base, only.env = TRUE) fepois(env = env) env = fenegbin(y ~ x1 + x2 | species, base, only.env = TRUE) fenegbin(env = env) env = femlm(y ~ x1 + x2 | species, base, only.env = TRUE) femlm(env = env) env = feNmlm(y ~ x1 + x2 | species, base, only.env = TRUE) feNmlm(env = env) # Now we check that modifications work as expected env = fepois(y ~ x1 + x2 | species, base, only.env = TRUE) est_w = fepois(y ~ x1 + x2 | species, base, weights = ~x3) assign("weights.value", base$x3, env) est_env_w = est_env(env = env) test(coef(est_w), coef(est_env_w)) #### #### xpd #### #### chunk("xpd") deparse_long = function(x) deparse(x, width.cutoff = 500) fml = xpd(y ~ x.[1:5] + z.[2:3]) test(deparse_long(fml), "y ~ x1 + x2 + x3 + x4 + x5 + z2 + z3") var = "a" fml = xpd(y ~ x.[var]) test(deparse_long(fml), "y ~ xa") vars = letters[1:5] fml = xpd(y ~ x.[vars] | fe1[[e, f]] + fe2[g]) test(deparse_long(fml), "y ~ xa + xb + xc + xd + xe | fe1[[e, f]] + fe2[g]") fml = xpd(y ~ ..x, ..x = "x.[vars]_sq") test(deparse_long(fml), "y ~ xa_sq + xb_sq + xc_sq + xd_sq + xe_sq") # Now we check it works in estimations base = setNames(iris, c("y", "x1", "x2", "x3", "species")) i = 1:2 fml = formula(feols(y ~ x.[i] | species[x3], base)) test(deparse_long(fml), "y ~ x1 + x2 | species + species[[x3]]") #### #### predict #### #### chunk("PREDICT") base = iris names(base) = c("y", "x1", "x2", "x3", "species") base$fe_bis = sample(letters, 150, TRUE) # # Same generative data # # Predict with fixed-effects res = feols(y ~ x1 | species + fe_bis, base) test(predict(res), predict(res, base)) res = fepois(y ~ x1 | species + fe_bis, base) test(predict(res), predict(res, base)) res = femlm(y ~ x1 | species + fe_bis, base) test(predict(res), predict(res, base)) # Predict with varying slopes -- That's normal that tolerance is high (because FEs are computed with low precision) res = feols(y ~ x1 | species + fe_bis[x3], base) test(predict(res), predict(res, base), "~", tol = 1e-4) res = fepois(y ~ x1 | species + fe_bis[x3], base) test(predict(res), predict(res, base), "~", tol = 1e-3) # Prediction with factors res = feols(y ~ x1 + i(species), base) test(predict(res), predict(res, base)) res = feols(y ~ x1 + i(species) + i(fe_bis), base) test(predict(res), predict(res, base)) quoi = head(base[, c("y", "x1", "species", "fe_bis")]) test(head(predict(res)), predict(res, quoi)) quoi$species = as.character(quoi$species) quoi$species[1:3] = "zz" test(predict(res, quoi), "err") # combine FEs res = feols(y ~ x1 | species^fe_bis, base) test(predict(res), predict(res, base)) # Handling NAs properly base_NA = data.frame(a = 1:5, b = c(3:6, NA), c = as.factor(c("a", "b", "a", "b", "a"))) res = feols(a ~ b + c, base_NA) test(length(predict(res, newdata = base_NA)), 5) # # prediction with lags # data(base_did) res = feols(y ~ x1 + l(x1), base_did, panel.id = ~ id + period) test(predict(res, sample = "original"), predict(res, base_did)) qui = sample(which(base_did$id %in% 1:5)) base_bis = base_did[qui, ] test(predict(res, sample = "original")[qui], predict(res, base_bis)) # # prediction with poly # res_poly = feols(y ~ poly(x1, 2), base) pred_all = predict(res_poly) pred_head = predict(res_poly, head(base, 20)) pred_tail = predict(res_poly, tail(base, 20)) test(head(pred_all, 20), pred_head) test(tail(pred_all, 20), pred_tail) # # "Predicting" fixed-effects # res = feols(y ~ x1 | species^fe_bis[x2], base, combine.quick = FALSE) obs_fe = predict(res, fixef = TRUE) fe_coef_all = fixef(res, sorted = FALSE) coef_fe = fe_coef_all[[1]] coef_vs = fe_coef_all[[2]] fe_names = paste0(base$species, "_", base$fe_bis) test(coef_fe[fe_names], obs_fe[, 1]) test(coef_vs[fe_names] * base$x2, obs_fe[, 2]) # with coef only obs_fe_coef = predict(res, fixef = TRUE, vs.coef = TRUE) test(coef_vs[fe_names], obs_fe_coef[, 2]) # # when new data contain single valued factors # est_singleF = feols(y ~ x1 + species, base) est_singleF_lm = lm(y ~ x1 + species, base) new_data = data.frame(x1 = 12:13, species = factor("setosa")) test(predict(est_singleF, newdata = new_data), predict(est_singleF_lm, newdata = new_data)) # # SE of prediction # a = lm(y ~ x1 + species, base) b = feols(y ~ x1 + species, base) test(predict(a, se.fit = TRUE)$se.fit, predict(b, se.fit = TRUE)$se.fit) test(predict(a, se.fit = TRUE, interval = "con")$fit[, 2], predict(b, se.fit = TRUE, interval = "con")$ci_low) test(suppressWarnings(predict(a, se.fit = TRUE, interval = "pre")$fit[, 2]), predict(b, se.fit = TRUE, interval = "pre")$ci_low) # With weights base$my_w = seq(0.01, 1, length.out = 150) aw = lm(y ~ x1 + species, base, weights = base$my_w) bw = feols(y ~ x1 + species, base, weights = ~my_w) test(predict(aw, se.fit = TRUE)$se.fit, predict(bw, se.fit = TRUE)$se.fit) test(predict(aw, se.fit = TRUE, interval = "con")$fit[, 2], predict(bw, se.fit = TRUE, interval = "con")$ci_low) test(suppressWarnings(predict(aw, se.fit = TRUE, interval = "pre")$fit[, 2]), predict(bw, se.fit = TRUE, interval = "pre")$ci_low) # # data contains poly/factor # est = feols(y ~ poly(x1, 2) + i(period, treat, 5) | id, data = base_did) new_data = base_did new_data$treat = 0 poly_x1 = poly(new_data$x1, 2) new_data$px1_1 = poly_x1[, 1] new_data$px1_2 = poly_x1[, 2] value = poly_x1 %*% coef(est)[1:2] + fixef(est)$id[as.character(new_data$id)] test(predict(est, newdata = new_data), value) # should work => same results as before new_data = base_did new_data$period = 5 test(predict(est, newdata = new_data), value) # should also work (differently from factor which raises an error) new_data = base_did new_data$period = 1955 test(predict(est, newdata = new_data), value) #### #### model.matrix #### #### chunk("Model matrix") base = iris names(base) = c("y1", "x1", "x2", "x3", "species") base$y2 = 10 + rnorm(150) + 0.5 * base$x1 base$x4 = rnorm(150) + 0.5 * base$y1 base$fe2 = rep(letters[1:15], 10) base$fe2[50:51] = NA base$y2[base$fe2 == "a" & !is.na(base$fe2)] = 0 base$x2[1:5] = NA base$x3[6] = NA base$fe3 = rep(letters[1:10], 15) base$id = rep(1:15, each = 10) base$time = rep(1:10, 15) base_bis = base[1:50, ] base_bis$id = rep(1:5, each = 10) base_bis$time = rep(1:10, 5) # NA removed res = feols(y1 ~ x1 + x2 + x3, base) m1 = model.matrix(res, type = "lhs") test(length(m1), res$nobs) # we check this is identical m1_na = model.matrix(res, type = "lhs", na.rm = FALSE) test(length(m1_na), res$nobs_origin) test(max(abs(m1_na - base$y1), na.rm = TRUE), 0) y = model.matrix(res, type = "lhs", data = base, na.rm = FALSE) X = model.matrix(res, type = "rhs", data = base, na.rm = FALSE) obs_rm = res$obs_selection$obsRemoved res_bis = lm.fit(X[obs_rm, ], y[obs_rm]) test(res_bis$coefficients, res$coefficients) # Lag res_lag = feols(y1 ~ l(x1, 1:2) + x2 + x3, base, panel = ~id + time) m_lag = model.matrix(res_lag) test(nrow(m_lag), nobs(res_lag)) # lag with subset m_lag_x1 = model.matrix(res_lag, subset = "x1") test(ncol(m_lag_x1), 2) # lag with subset, new data mbis_lag_x1 = model.matrix(res_lag, base_bis[, c("x1", "x2", "id", "time")], subset = TRUE) # l(x1, 1) + l(x1, 2) + x2 test(ncol(mbis_lag_x1), 3) # 13 NAs: 2 per ID for the lags, 3 for x2 test(nrow(mbis_lag_x1), 37) # With poly res_poly = feols(y1 ~ poly(x1, 2), base) m_poly_old = model.matrix(res_poly) m_poly_new = model.matrix(res_poly, base_bis) test(m_poly_old[1:50, 3], m_poly_new[, 3]) # fixef res = feols(y1 ~ x1 + x2 + x3 | species + fe2, base) m_fe = model.matrix(res, type = "fixef") test(ncol(m_fe), 2) # lhs m_lhs = model.matrix(res, type = "lhs", na.rm = FALSE) test(m_lhs, base$y1) # IV res_iv = feols(y1 ~ x1 | x2 ~ x3, base) m_rhs1 = model.matrix(res_iv, type = "iv.rhs1") test(colnames(m_rhs1)[-1], c("x3", "x1")) m_rhs2 = model.matrix(res_iv, type = "iv.rhs2") test(colnames(m_rhs2)[-1], c("fit_x2", "x1")) m_endo = model.matrix(res_iv, type = "iv.endo") test(colnames(m_endo), "x2") m_exo = model.matrix(res_iv, type = "iv.exo") test(colnames(m_exo)[-1], "x1") m_inst = model.matrix(res_iv, type = "iv.inst") test(colnames(m_inst), "x3") # several res_mult = feols(y1 ~ x1 | species | x2 ~ x3, base) m_lhs_rhs_fixef = model.matrix(res_mult, type = c("lhs", "iv.rhs2", "fixef"), na.rm = FALSE) test(names(m_lhs_rhs_fixef), c("y1", "fit_x2", "x1", "species")) #### #### fitstat #### #### chunk("fitstat") base = iris names(base) = c("y", "x1", "x_endo_1", "x_inst_1", "fe") set.seed(2) base$x_inst_2 = 0.2 * base$y + 0.2 * base$x_endo_1 + rnorm(150, sd = 0.5) base$x_endo_2 = 0.2 * base$y - 0.2 * base$x_inst_1 + rnorm(150, sd = 0.5) # Checking a basic estimation est_iv = feols(y ~ x1 | x_endo_1 + x_endo_2 ~ x_inst_1 + x_inst_2, base) fitstat(est_iv, ~ f + ivf + ivf2 + wald + ivwald + ivwald2 + wh + sargan + rmse + g + n + ll + sq.cor + r2) est_fe = feols(y ~ x1 | fe, base) fitstat(est_fe, ~ wf) #### #### confint #### #### chunk("confint") base = setNames(iris, c("y", "x1", "x2", "x3", "species")) est = feols(y ~ x1 + x2 | species, base) test(nrow(confint(est)), 2) test(nrow(confint(est, "x1")), 1) est_pois = fepois(y ~ x1 | species, base) test(nrow(confint(est_pois)), 1) est_iv = feols(y ~ x1 | species | x2 ~ x3, base) test(nrow(confint(est_iv)), 2) # # coefplot confidence intervals # est_coefplot_prms = coefplot(est, only.params = TRUE)$prms[, 2:3] test(confint(est), est_coefplot_prms) est_pois_coefplot_prms = coefplot(est_pois, only.params = TRUE)$prms[, 2:3] test(confint(est_pois), est_pois_coefplot_prms) est_iv_coefplot_prms = coefplot(est_iv, only.params = TRUE)$prms[, 2:3] test(confint(est_iv), est_iv_coefplot_prms) # ... changing the df.t argument est = feols(y ~ x1 + x2, base) est_coefplot_prms_larger = coefplot(est, df.t = 5, only.params = TRUE)$prms[, 2:3] test(all(confint(est)[, 1] > est_coefplot_prms_larger[, 1]), TRUE) est_coefplot_prms_smaller = coefplot(est, df.t = Inf, only.params = TRUE)$prms[, 2:3] test(all(confint(est)[, 1] < est_coefplot_prms_smaller[, 1]), TRUE) # ... checking with non fixest objects est = feols(y ~ x1 + x2, base) mat_default = coefplot(coeftable(est), only.params = TRUE)$prms[, 2:3] est_inf = coefplot(est, df.t = Inf, only.params = TRUE)$prms[, 2:3] test(mat_default, est_inf) mat_custom = coefplot(coeftable(est), df.t = 5, only.params = TRUE)$prms[, 2:3] est_custom = coefplot(est, df.t = 5, only.params = TRUE)$prms[, 2:3] test(mat_custom, est_custom) #### #### etable #### #### chunk("etable") # VERY hard to make proper tests... base = setNames(iris, c("y", "x1", "x2", "x3", "species")) est_onlyFE = feols(y ~ 1 | species, base) est = feols(y ~ x.[1:3], base) et0 = etable(est_onlyFE) test(nrow(et0), 7) et1 = etable(est_onlyFE, est) test(nrow(et1), 12) et2 = etable(est_onlyFE, est, se.below = TRUE) test(nrow(et2), 16) # Latex escaping cpp_escape_markup = fixest:::cpp_escape_markup # MD markup test(cpp_escape_markup("**bonjour** *les* ***gens * \\***heureux***"), "\\textbf{bonjour} \\textit{les} \\textbf{\\textit{gens * ***heureux}}") # Escaping + markup in equations test(cpp_escape_markup("$x_5*3^2$ est **different** de x_5*3^2"), "$x_5*3^2$ est \\textbf{different} de x\\_5*3\\^2") # single $ escaping + # % test(cpp_escape_markup("Rule #1: this $ should be escaped! this % too!"), "Rule \\#1: this \\$ should be escaped! this \\% too!") # dirty $ => user mistake test(cpp_escape_markup("$there$ are *too many $ here*!"), "$there$ are \\textit{too many \\$ here}!") # random, stacking test(cpp_escape_markup("#%_&^*hi$*$ *there**"), "\\#\\%\\_\\&\\^\\textit{hi$*$ }there**") # values already escaped test(cpp_escape_markup("\\$this_is **not** an\\^equation\\$. But $this&one, \\$, * is *$ *is*."), "\\$this\\_is \\textbf{not} an\\^equation\\$. But $this&one, \\$, * is *$ \\textit{is}.")