diff --git a/mlair/plotting/postprocessing_plotting.py b/mlair/plotting/postprocessing_plotting.py
index 2c7d8fdedb2720b1276b77a5e817723094ecf03d..c96026736074bc29497073e5669d557fdc6d647d 100644
--- a/mlair/plotting/postprocessing_plotting.py
+++ b/mlair/plotting/postprocessing_plotting.py
@@ -726,7 +726,8 @@ class PlotCompetitiveSkillScore(AbstractPlotClass):
 
     def _plot(self):
         """Plot skill scores of the comparisons."""
-        fig, ax = plt.subplots()
+        size = max([len(np.unique(self._data.comparison)), 6])
+        fig, ax = plt.subplots(figsize=(size, size * 0.8))
         order = self._create_pseudo_order()
         sns.boxplot(x="comparison", y="data", hue="ahead", data=self._data, whis=1., ax=ax, palette="Blues_d",
                     showmeans=True, meanprops={"markersize": 3, "markeredgecolor": "k"}, flierprops={"marker": "."},
@@ -735,7 +736,7 @@ class PlotCompetitiveSkillScore(AbstractPlotClass):
 
         ax.set(ylabel="skill score", xlabel="competing models", title="summary of all stations", ylim=self._lim())
         handles, _ = ax.get_legend_handles_labels()
-        plt.xticks(rotation=20)
+        plt.xticks(rotation=90)
         ax.legend(handles, self._labels)
         plt.tight_layout()
 
diff --git a/mlair/run_modules/experiment_setup.py b/mlair/run_modules/experiment_setup.py
index e772bbaaba5a7618b95f345dcb7056616c56403e..34da6cb33828d8fd2b34d15dd50da3e30c8af17e 100644
--- a/mlair/run_modules/experiment_setup.py
+++ b/mlair/run_modules/experiment_setup.py
@@ -346,7 +346,7 @@ class ExperimentSetup(RunEnvironment):
         self._set_param("neighbors", ["DEBW030"])  # TODO: just for testing
 
         # set competitors
-        self._set_param("competitors", helpers.to_list(competitors), default=[])
+        self._set_param("competitors", competitors, default=[])
         competitor_path_default = os.path.join(self.data_store.get("data_path"), "competitors",
                                                "_".join(self.data_store.get("target_var")))
         self._set_param("competitor_path", competitor_path, default=competitor_path_default)
diff --git a/mlair/run_modules/post_processing.py b/mlair/run_modules/post_processing.py
index ebcf105f3b4b6c36b95d003275a2e3e52c78e61e..020f0a42b9e205800b39ccbfdec20cbba8364f1f 100644
--- a/mlair/run_modules/post_processing.py
+++ b/mlair/run_modules/post_processing.py
@@ -15,7 +15,7 @@ import xarray as xr
 
 from mlair.data_handler import BootStraps, KerasIterator
 from mlair.helpers.datastore import NameNotFoundInDataStore
-from mlair.helpers import TimeTracking, statistics, extract_value, remove_items
+from mlair.helpers import TimeTracking, statistics, extract_value, remove_items, to_list
 from mlair.model_modules.linear_model import OrdinaryLeastSquaredModel
 from mlair.model_modules.model_class import AbstractModelClass
 from mlair.plotting.postprocessing_plotting import PlotMonthlySummary, PlotStationMap, PlotClimatologicalSkillScore, \
@@ -81,7 +81,7 @@ class PostProcessing(RunEnvironment):
         self.skill_scores = None
         self.bootstrap_skill_scores = None
         self.competitor_path = self.data_store.get("competitor_path")
-        self.competitors = self.data_store.get_default("competitors", default=[])
+        self.competitors = to_list(self.data_store.get_default("competitors", default=[]))
         self.forecast_indicator = "nn"
         self._run()