Assert frequency >= 1 in InputData

meridian/data/input_data.py

@@ -292,6 +292,19 @@ def __post_init__(self):
     self._validate_times()
     self._validate_geos()
     self._validate_no_negative_values()
+    self._validate_frequencies()
+
+  def _validate_frequencies(self) -> None:
+    """Validates that frequency values are at least 1."""
+    for field, loggable_field in [
+        (constants.FREQUENCY, "Frequency"),
+        (constants.ORGANIC_FREQUENCY, "Organic Frequency"),
+    ]:
+      da = getattr(self, field)
+      if da is not None and (da.values < 1).any():
+        raise ValueError(
+            f"{loggable_field} values must be at least 1."
+        )
 
   def _coerce_object_arrays_to_float(self):
     """Coerces object-typed DataArrays to float."""
@@ -619,9 +632,7 @@ def _validate_no_negative_values(self) -> None:
         constants.MEDIA_SPEND: "Media Spend",
         constants.RF_SPEND: "RF Spend",
         constants.REACH: "Reach",
-        constants.FREQUENCY: "Frequency",
         constants.ORGANIC_REACH: "Organic Reach",
-        constants.ORGANIC_FREQUENCY: "Organic Frequency",
         constants.REVENUE_PER_KPI: "Revenue per KPI",
         constants.KPI: "KPI",
     }

meridian/data/input_data_test.py

@@ -259,12 +259,6 @@ def test_validate_kpi_wrong_type(self):
           name="Reach",
           kpi_type=constants.REVENUE,
       ),
-      dict(
-          testcase_name="frequency",
-          field=constants.FREQUENCY,
-          name="Frequency",
-          kpi_type=constants.REVENUE,
-      ),
       dict(
           testcase_name="kpi",
           field=constants.KPI,
@@ -278,6 +272,7 @@ def test_validate_kpi_wrong_type(self):
           kpi_type=constants.NON_REVENUE,
       ),
   )
+
   def test_validate_no_negative_values(
       self, field: str, name: str, kpi_type: str
   ):
@@ -301,6 +296,24 @@ def test_validate_no_negative_values(
           frequency=maybe_flip(self.lagged_frequency, constants.FREQUENCY),
       )
 
+  def test_validate_frequency_threshold(self):
+    with self.assertRaisesRegex(
+        ValueError,
+        expected_regex="Frequency values must be at least 1.",
+    ):
+      frequency = self.not_lagged_frequency.copy(deep=True)
+      frequency.values[0, 0, 0] = 0.5
+      input_data.InputData(
+          controls=self.not_lagged_controls,
+          kpi=self.not_lagged_kpi,
+          kpi_type=constants.NON_REVENUE,
+          population=self.population,
+          revenue_per_kpi=self.revenue_per_kpi,
+          reach=self.not_lagged_reach,
+          frequency=frequency,
+          rf_spend=self.rf_spend,
+      )
+
   def test_validate_media_channels_duplicate_names(self):
     media = test_utils.random_media_da(
         n_geos=self.n_geos,
@@ -2176,24 +2189,12 @@ def _verify_copy(self, original: input_data.InputData, deep: bool):
           name="Reach",
           kpi_type=constants.NON_REVENUE,
       ),
-      dict(
-          testcase_name="frequency",
-          field=constants.FREQUENCY,
-          name="Frequency",
-          kpi_type=constants.NON_REVENUE,
-      ),
       dict(
           testcase_name="organic_reach",
           field=constants.ORGANIC_REACH,
           name="Organic Reach",
           kpi_type=constants.NON_REVENUE,
       ),
-      dict(
-          testcase_name="organic_frequency",
-          field=constants.ORGANIC_FREQUENCY,
-          name="Organic Frequency",
-          kpi_type=constants.NON_REVENUE,
-      ),
       dict(
           testcase_name="kpi",
           field=constants.KPI,

meridian/data/test_utils.py

@@ -1142,6 +1142,7 @@ def random_frequency_da(
       abs(np.random.normal(3, 5, size=(n_geos, n_media_times, n_rf_channels)))
       + nonzero_shift
   )
+  frequency = np.maximum(frequency, 1.0)
 
   channels = (
       explicit_rf_channel_names