title: Customizing labels in SHAPforxgboost plots
body: <p>I'm creating some plots of SHAP-scores for visualizing a model I created with xgboost. I've used the SHAPforxgboost package which has worked very well, and I now want to use the figures (especially the one from shap.plot.summary()) in a text document I'm writing. However, the font sizes of the labels/titles on the x and y-axes are very small and I was wondering if there was a way I could make these larger and more readable.</p>
  
  <p>I've used a very similar setup as shown here; <a href="https://www.rdocumentation.org/packages/SHAPforxgboost/versions/0.0.2" rel="nofollow noreferrer">https://www.rdocumentation.org/packages/SHAPforxgboost/versions/0.0.2</a> :</p>
  
  <pre><code>library("SHAPforxgboost")
  y_var &lt;-  "diffcwv"
  dataX &lt;- dataXY_df[,-..y_var]
  # hyperparameter tuning results
  param_dart &lt;- list(objective = "reg:linear",  # For regression
                     nrounds = 366,
                     eta = 0.018,
                     max_depth = 10,
                     gamma = 0.009,
                     subsample = 0.98,
                     colsample_bytree = 0.86)
  
  mod &lt;- xgboost::xgboost(data = as.matrix(dataX), label = as.matrix(dataXY_df[[y_var]]), 
                         xgb_param = param_dart, nrounds = param_dart$nrounds,
                         verbose = FALSE, nthread = parallel::detectCores() - 2,
                         early_stopping_rounds = 8)
  
  # To return the SHAP values and ranked features by mean|SHAP|
  shap_values &lt;- shap.values(xgb_model = mod, X_train = dataX)
  # The ranked features by mean |SHAP|
  shap_values$mean_shap_score
  
  # To prepare the long-format data:
  shap_long &lt;- shap.prep(xgb_model = mod, X_train = dataX)
  # is the same as: using given shap_contrib
  shap_long &lt;- shap.prep(shap_contrib = shap_values$shap_score, X_train = dataX)
  # (Notice that there will be a data.table warning from `melt.data.table` due to `dayint` coerced from integer to double)
  
  # **SHAP summary plot**
  shap.plot.summary(shap_long)
  </code></pre>
  
  <p>The output of shap.plot.summary() is: <a href="https://i.stack.imgur.com/Y1akr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Y1akr.png" alt="something like this"></a></p>
  
  <p>More specifically, I would be interested in increasing the font size of each descriptor on the y-axis</p>