title: ggarrange() for ggplots overlap annotate() text
body: <p>I'm having a problem with plots using <code>ggarrange()</code> from <code>egg</code> library. When a I visualize every single plot (using RStudio), they are perfect. However, when I merged three plots in one single plot, the relative size of each grid change with respect to the size of every plot, and also, annotated texts get overlap one to another, and relative sizes of fonts change. It seems to be more a problem of visualization than of code, but I don't know.</p>
  
  <pre class="lang-r prettyprint-override"><code>library(ggplot2)
  library(egg)
  
  data &lt;-
    structure(list(Treatment = structure(c(1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 4L, 4L, 4L, 4L, 4L),
                                         .Label = c("A","B", "C", "D"),
                                         class = "factor"),
                   Var1 = c(10L, 12L, 13L, 9L, 14L, 1L, 2L, 1L, 4L, 5L, 5L, 4L, 3L, 8L, 4L, 20L, 20L, 26L, 24L, 17L),
                   Var2 = c(2.5, 2.6, 2.3, 2.8, 2.9, 1.5, 1.3, 1.5, 1.4, 1.3, 1.6, 1.7, 1.6, 1.8, 1.6, 3.2, 3.5, 3.3, 3.2, 3.1),
                   Var3 = c(1.1,1.2, 1.1, 1.1, 1.2, 1.4, 1.5, 1.4, 1.5, 1.4, 1.3, 1.3, 1.2, 1.3, 1.3, 0.9, 0.85, 0.9, 0.8, 0.85)),
              class = "data.frame",
              row.names = c(NA, -20L))
  
  figura2a &lt;-
    ggplot(data, aes(x = Var2, y = Var1)) +
    geom_point(aes(
      color = Treatment,
      shape = Treatment,
      size = 2.5
    )) +
    theme(legend.position = "bottom") +
    geom_smooth(method = 'lm',
                colour = "black",
                se = FALSE) +
    scale_colour_manual(values = c(
      "lightsteelblue4",
      "salmon",
      "purple3",
      "royalblue2",
      "seagreen3"
    )) +
    scale_shape_manual(values = c(15, 16, 25, 18, 17)) +
    theme_light() +
    theme(
      axis.text.x = element_text(colour = "black", size = 22),
      axis.text.y = element_text(colour = "black", size = 22)
    ) +
    theme(text = element_text(
      size = 22,
      family = "Arial",
      color = "black"
    )) +
    theme(legend.title = element_text(size = 20, color = "black"),
          legend.text = element_text(size = 20)) +
    scale_size(guide = 'none') +
    guides(shape = guide_legend(override.aes = list(size = 4))) +
    xlab("Var2") +
    ylab("Var1") +
    theme(legend.position = "none") +
    annotate(
      geom = "text",
      x = 3,
      y = 4,
      label = "R^2 == 0.8639",
      parse = TRUE,
      color = "black",
      size = 5
    ) +
    annotate(
      geom = "text",
      x = 3,
      y = 5.5,
      label = "p &lt; 0.001",
      color = "black",
      size = 5.5,
      fontface = 'italic',
      check_overlap = TRUE
    )
  figura2a
  </code></pre>
  
  <p><img src="https://i.imgur.com/llbcjNU.png" alt=""></p>
  
  <pre class="lang-r prettyprint-override"><code>figura2b &lt;-
    ggplot(data, aes(x = Var3, y = Var1)) +
    geom_point(aes(
      color = Treatment,
      shape = Treatment,
      size = 2.5
    )) +
    theme(legend.position = "bottom") +
    geom_smooth(method = 'lm',
                colour = "black",
                se = FALSE) +
    scale_colour_manual(values = c(
      "lightsteelblue4",
      "salmon",
      "purple3",
      "royalblue2",
      "seagreen3"
    )) +
    scale_shape_manual(values = c(15, 16, 25, 18, 17)) +
    theme_light() +
    theme(
      axis.text.x = element_text(colour = "black", size = 22),
      axis.text.y = element_text(colour = "black", size = 22)
    ) +
    theme(text = element_text(
      size = 22,
      family = "Arial",
      color = "black"
    )) +
    theme(legend.title = element_text(size = 20, color = "black"),
          legend.text = element_text(size = 20)) +
    scale_size(guide = 'none') +
    guides(shape = guide_legend(override.aes = list(size = 4))) +
    xlab("Var3") +
    ylab("Var1") +
    theme(legend.position = "none") +
    annotate(
      geom = "text",
      x = 1.2,
      y = 22,
      label = "R^2 == 0.8252",
      parse = TRUE,
      color = "black",
      size = 5
    ) +
    annotate(
      geom = "text",
      x = 1.2,
      y = 20,
      label = "p &lt; 0.001",
      color = "black",
      size = 5.5,
      fontface = 'italic'
    )
  figura2b
  </code></pre>
  
  <p><img src="https://i.imgur.com/BXfyyDR.png" alt=""></p>
  
  <pre class="lang-r prettyprint-override"><code>figura2 &lt;- ggarrange(figura2a, figura2b, ncol = 1, nrow = 2)
  </code></pre>
  
  <p><img src="https://i.imgur.com/bQvGsEl.png" alt=""></p>
  
  <p><sup>Created on 2020-05-16 by the <a href="https://reprex.tidyverse.org" rel="nofollow noreferrer">reprex package</a> (v0.3.0)</sup></p>