add tests

Author: juanitorduz

pymc_marketing/mmm/mmm.py

@@ -66,10 +66,6 @@
 
 # Constants
 DEFAULT_HDI_PROB = 0.94
-DEFAULT_LOWER_QUANTILE = 0.025
-DEFAULT_UPPER_QUANTILE = 0.975
-DEFAULT_QUANTILE = 0.5
-DEFAULT_N_PERCENTILES = 30
 
 
 class BaseMMM(BaseValidateMMM):
@@ -449,9 +445,11 @@ def _compute_scales(self) -> None:
         self.channel_scale = self._compute_scale_for_data(
             channel_data, self.scaling.channel.method, axis=0
         )
-        self.target_scale = self._compute_scale_for_data(
+        target_scale = self._compute_scale_for_data(
             target_data, self.scaling.target.method, axis=None
         )
+        # Ensure target_scale is a Python float (convert from numpy scalar if needed)
+        self.target_scale = float(target_scale)
 
     def create_idata_attrs(self) -> dict[str, str]:
         """Create attributes for the inference data.