title: ggplot error bars are horizontal but should be vertical
body: <p>I created two plots with ggplot containing errorbars. My first plot shows the errorbars in the vertical direction like they should be but the second plot has them facing horizontally even though I used the same code. How can I change the direction of the error bars? They should both run vertically.</p>
  
  <p>Plot 1: </p>
  
  <pre><code>head(arsum)
      ss   BV   N    a_rmse        sd          se          ci
  1  300 .053 600 0.4490948 0.1939080 0.007916261 0.015547000
  2  300 0.11 600 0.4326376 0.1876572 0.007661074 0.015045831
  3  300 0.25 600 0.4028272 0.1758211 0.007177866 0.014096842
  4  300 0.43 600 0.3736950 0.1587006 0.006478925 0.012724171
  5  300 1.00 600 0.3328419 0.1163379 0.004749474 0.009327646
  6 1000 .053 600 0.3211591 0.1379862 0.005633262 0.011063344
  
  ggplot(data=arsum, aes(x=BV, y=a_rmse, color=ss, group=ss))+
     geom_errorbar(aes(ymin=a_rmse-se, ymax=a_rmse+se), width=.1)+
     geom_point()+
     geom_line()+
     geom_hline(yintercept=0)+
     ggtitle("Interaction Plot Single Level Discrimination")+
     xlab("ICC")+
     ylab("Discrimination RMSE")+
     labs(colour = "Sample Size") 
  </code></pre>
  
  <p>Plot 2: </p>
  
  <pre><code>head(twsum)
     ICC items    N    w_rmse         sd           se           ci
  1 0.05    10 2915 0.7025752 0.02322448 0.0004301566 0.0008434419
  2 0.05    20 2905 0.6053087 0.02072466 0.0003845158 0.0007539515
  3 0.05    50 2863 0.4738864 0.02033279 0.0003800024 0.0007451061
  4 0.05    70 2849 0.4368722 0.02125809 0.0003982703 0.0007809273
  5  0.1    10 2878 0.7155422 0.02341178 0.0004364043 0.0008556967
  6  0.1    20 2907 0.6272082 0.02283895 0.0004235978 0.0008305823
  
  ggplot(data=twsum, aes(x=ICC, y=w_rmse, color=items, group=items))+
      geom_errorbar(aes(ymin=w_rmse-se, ymax=w_rmse+se), width=.1)+
      geom_point()+
      geom_line()+
      geom_hline(yintercept=0)+
      ggtitle("Interaction Plot Single Level Within-cluster Theta RMSE")+
      xlab("ICC")+
      ylab("Within-cluster Theta RMSE")+
      labs(colour = "Number of \nItems") 
  </code></pre>