Glance accepts a model object and returns a tibble::tibble() with exactly one row of model summaries. The summaries are typically goodness of fit measures, p-values for hypothesis tests on residuals, or model convergence information.

Glance never returns information from the original call to the modeling function. This includes the name of the modeling function or any arguments passed to the modeling function.

Glance does not calculate summary measures. Rather, it farms out these computations to appropriate methods and gathers the results together. Sometimes a goodness of fit measure will be undefined. In these cases the measure will be reported as NA.

Glance returns the same number of columns regardless of whether the model matrix is rank-deficient or not. If so, entries in columns that no longer have a well-defined value are filled in with an NA of the appropriate type.

# S3 method for lm
glance(x, ...)

Arguments

x

An lm object created by stats::lm().

...

Additional arguments. Not used. Needed to match generic signature only. Cautionary note: Misspelled arguments will be absorbed in ..., where they will be ignored. If the misspelled argument has a default value, the default value will be used. For example, if you pass conf.level = 0.9, all computation will proceed using conf.level = 0.95. Additionally, if you pass newdata = my_tibble to an augment() method that does not accept a newdata argument, it will use the default value for the data argument.

See also

Value

A tibble::tibble() with exactly one row and columns:

adj.r.squared

Adjusted R squared statistic, which is like the R squared statistic except taking degrees of freedom into account.

AIC

Akaike's Information Criterion for the model.

BIC

Bayesian Information Criterion for the model.

deviance

Deviance of the model.

df.residual

Residual degrees of freedom.

logLik

The log-likelihood of the model. [stats::logLik()] may be a useful reference.

nobs

Number of observations used.

p.value

P-value corresponding to the test statistic.

r.squared

R squared statistic, or the percent of variation explained by the model. Also known as the coefficient of determination.

sigma

Estimated standard error of the residuals.

statistic

Test statistic.

df

The degrees for freedom from the numerator of the overall F-statistic. This is new in broom 0.7.0. Previously, this reported the rank of the design matrix, which is one more than the numerator degrees of freedom of the overall F-statistic.

Examples

library(ggplot2) library(dplyr) mod <- lm(mpg ~ wt + qsec, data = mtcars) tidy(mod)
#> # A tibble: 3 x 5 #> term estimate std.error statistic p.value #> <chr> <dbl> <dbl> <dbl> <dbl> #> 1 (Intercept) 19.7 5.25 3.76 7.65e- 4 #> 2 wt -5.05 0.484 -10.4 2.52e-11 #> 3 qsec 0.929 0.265 3.51 1.50e- 3
glance(mod)
#> # A tibble: 1 x 12 #> r.squared adj.r.squared sigma statistic p.value df logLik AIC BIC #> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #> 1 0.826 0.814 2.60 69.0 9.39e-12 2 -74.4 157. 163. #> # … with 3 more variables: deviance <dbl>, df.residual <int>, nobs <int>
# coefficient plot d <- tidy(mod, conf.int = TRUE) ggplot(d, aes(estimate, term, xmin = conf.low, xmax = conf.high, height = 0)) + geom_point() + geom_vline(xintercept = 0, lty = 4) + geom_errorbarh()
augment(mod)
#> # A tibble: 32 x 10 #> .rownames mpg wt qsec .fitted .resid .std.resid .hat .sigma .cooksd #> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #> 1 Mazda RX4 21 2.62 16.5 21.8 -0.815 -0.325 0.0693 2.64 2.63e-3 #> 2 Mazda RX4… 21 2.88 17.0 21.0 -0.0482 -0.0190 0.0444 2.64 5.59e-6 #> 3 Datsun 710 22.8 2.32 18.6 25.3 -2.53 -1.00 0.0607 2.60 2.17e-2 #> 4 Hornet 4 … 21.4 3.22 19.4 21.6 -0.181 -0.0716 0.0576 2.64 1.05e-4 #> 5 Hornet Sp… 18.7 3.44 17.0 18.2 0.504 0.198 0.0389 2.64 5.29e-4 #> 6 Valiant 18.1 3.46 20.2 21.1 -2.97 -1.20 0.0957 2.58 5.10e-2 #> 7 Duster 360 14.3 3.57 15.8 16.4 -2.14 -0.857 0.0729 2.61 1.93e-2 #> 8 Merc 240D 24.4 3.19 20 22.2 2.17 0.872 0.0791 2.61 2.18e-2 #> 9 Merc 230 22.8 3.15 22.9 25.1 -2.32 -1.07 0.295 2.59 1.59e-1 #> 10 Merc 280 19.2 3.44 18.3 19.4 -0.185 -0.0728 0.0358 2.64 6.55e-5 #> # … with 22 more rows
augment(mod, mtcars, interval = "confidence")
#> # A tibble: 32 x 20 #> .rownames mpg cyl disp hp drat wt qsec vs am gear carb #> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #> 1 Mazda RX4 21 6 160 110 3.9 2.62 16.5 0 1 4 4 #> 2 Mazda RX… 21 6 160 110 3.9 2.88 17.0 0 1 4 4 #> 3 Datsun 7… 22.8 4 108 93 3.85 2.32 18.6 1 1 4 1 #> 4 Hornet 4… 21.4 6 258 110 3.08 3.22 19.4 1 0 3 1 #> 5 Hornet S… 18.7 8 360 175 3.15 3.44 17.0 0 0 3 2 #> 6 Valiant 18.1 6 225 105 2.76 3.46 20.2 1 0 3 1 #> 7 Duster 3… 14.3 8 360 245 3.21 3.57 15.8 0 0 3 4 #> 8 Merc 240D 24.4 4 147. 62 3.69 3.19 20 1 0 4 2 #> 9 Merc 230 22.8 4 141. 95 3.92 3.15 22.9 1 0 4 2 #> 10 Merc 280 19.2 6 168. 123 3.92 3.44 18.3 1 0 4 4 #> # … with 22 more rows, and 8 more variables: .fitted <dbl>, .lower <dbl>, #> # .upper <dbl>, .resid <dbl>, .std.resid <dbl>, .hat <dbl>, .sigma <dbl>, #> # .cooksd <dbl>
# predict on new data newdata <- mtcars %>% head(6) %>% mutate(wt = wt + 1) augment(mod, newdata = newdata)
#> # A tibble: 6 x 13 #> mpg cyl disp hp drat wt qsec vs am gear carb .fitted #> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #> 1 21 6 160 110 3.9 3.62 16.5 0 1 4 4 16.8 #> 2 21 6 160 110 3.9 3.88 17.0 0 1 4 4 16.0 #> 3 22.8 4 108 93 3.85 3.32 18.6 1 1 4 1 20.3 #> 4 21.4 6 258 110 3.08 4.22 19.4 1 0 3 1 16.5 #> 5 18.7 8 360 175 3.15 4.44 17.0 0 0 3 2 13.1 #> 6 18.1 6 225 105 2.76 4.46 20.2 1 0 3 1 16.0 #> # … with 1 more variable: .resid <dbl>
# ggplot2 example where we also construct 95% prediction interval mod2 <- lm(mpg ~ wt, data = mtcars) ## simpler bivariate model since we're plotting in 2D au <- augment(mod2, newdata = newdata, interval = "prediction") ggplot(au, aes(wt, mpg)) + geom_point() + geom_line(aes(y = .fitted)) + geom_ribbon(aes(ymin = .lower, ymax = .upper), col = NA, alpha = 0.3)
# predict on new data without outcome variable. Output does not include .resid newdata <- newdata %>% select(-mpg)
#> Error in select(., -mpg): unused argument (-mpg)
augment(mod, newdata = newdata)
#> # A tibble: 6 x 13 #> mpg cyl disp hp drat wt qsec vs am gear carb .fitted #> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> #> 1 21 6 160 110 3.9 3.62 16.5 0 1 4 4 16.8 #> 2 21 6 160 110 3.9 3.88 17.0 0 1 4 4 16.0 #> 3 22.8 4 108 93 3.85 3.32 18.6 1 1 4 1 20.3 #> 4 21.4 6 258 110 3.08 4.22 19.4 1 0 3 1 16.5 #> 5 18.7 8 360 175 3.15 4.44 17.0 0 0 3 2 13.1 #> 6 18.1 6 225 105 2.76 4.46 20.2 1 0 3 1 16.0 #> # … with 1 more variable: .resid <dbl>
au <- augment(mod, data = mtcars) ggplot(au, aes(.hat, .std.resid)) + geom_vline(size = 2, colour = "white", xintercept = 0) + geom_hline(size = 2, colour = "white", yintercept = 0) + geom_point() + geom_smooth(se = FALSE)
#> `geom_smooth()` using method = 'loess' and formula 'y ~ x'
plot(mod, which = 6)
ggplot(au, aes(.hat, .cooksd)) + geom_vline(xintercept = 0, colour = NA) + geom_abline(slope = seq(0, 3, by = 0.5), colour = "white") + geom_smooth(se = FALSE) + geom_point()
#> `geom_smooth()` using method = 'loess' and formula 'y ~ x'
# column-wise models a <- matrix(rnorm(20), nrow = 10) b <- a + rnorm(length(a)) result <- lm(b ~ a) tidy(result)
#> # A tibble: 6 x 6 #> response term estimate std.error statistic p.value #> <chr> <chr> <dbl> <dbl> <dbl> <dbl> #> 1 Y1 (Intercept) 0.591 0.359 1.64 0.144 #> 2 Y1 a1 0.971 0.284 3.42 0.0111 #> 3 Y1 a2 -0.0905 0.414 -0.219 0.833 #> 4 Y2 (Intercept) 0.0105 0.350 0.0299 0.977 #> 5 Y2 a1 0.00789 0.277 0.0285 0.978 #> 6 Y2 a2 1.90 0.403 4.72 0.00216