diff --git a/.idea/runConfigurations/unimore_bda_6.xml b/.idea/runConfigurations/unimore_bda_6.xml
index 120005b..0adffd8 100644
--- a/.idea/runConfigurations/unimore_bda_6.xml
+++ b/.idea/runConfigurations/unimore_bda_6.xml
@@ -1,16 +1,18 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="unimore_bda_6" type="PythonConfigurationType" factoryName="Python" nameIsGenerated="true">
     <module name="unimore-bda-6" />
-    <option name="INTERPRETER_OPTIONS" value="-O" />
+    <option name="INTERPRETER_OPTIONS" value="" />
     <option name="PARENT_ENVS" value="true" />
     <envs>
       <env name="CONFIRM_OVERWRITE" value="False" />
       <env name="NLTK_DATA" value="./data/nltk" />
       <env name="PYTHONUNBUFFERED" value="1" />
-      <env name="TENSORFLOW_EPOCHS" value="4" />
       <env name="TF_CPP_MIN_LOG_LEVEL" value="2" />
-      <env name="WORKING_SET_SIZE" value="1000000" />
+      <env name="WORKING_SET_SIZE" value="100000" />
       <env name="XLA_FLAGS" value="--xla_gpu_cuda_data_dir=/opt/cuda" />
+      <env name="TRAINING_SET_SIZE" value="100" />
+      <env name="VALIDATION_SET_SIZE" value="25" />
+      <env name="EVALUATION_SET_SIZE" value="100" />
     </envs>
     <option name="SDK_HOME" value="$PROJECT_DIR$/.venv/bin/python" />
     <option name="SDK_NAME" value="Poetry (unimore-bda-6)" />
diff --git a/unimore_bda_6/__main__.py b/unimore_bda_6/__main__.py
index d492b6b..2ffb248 100644
--- a/unimore_bda_6/__main__.py
+++ b/unimore_bda_6/__main__.py
@@ -8,7 +8,7 @@ from .config import config
 from .database import mongo_client_from_config, reviews_collection, sample_reviews_polar, sample_reviews_varied
 from .analysis import NLTKSentimentAnalyzer, TensorflowCategorySentimentAnalyzer, TensorflowPolarSentimentAnalyzer
 from .analysis.base import TrainingFailedError
-from .tokenizer import PlainTokenizer, LowercaseTokenizer, NLTKWordTokenizer, PottsTokenizer, PottsTokenizerWithNegation
+from .tokenizer import PlainTokenizer, LowercaseTokenizer, NLTKWordTokenizer, PottsTokenizer, PottsTokenizerWithNegation, HuggingBertTokenizer
 from .gathering import Caches
 
 log = logging.getLogger(__name__)
@@ -38,20 +38,21 @@ def main():
             slog.debug("Selected sample_func: %s", sample_func.__name__)
 
             for SentimentAnalyzer in [
+                NLTKSentimentAnalyzer,
                 TensorflowPolarSentimentAnalyzer,
                 TensorflowCategorySentimentAnalyzer,
-                NLTKSentimentAnalyzer,
             ]:
 
                 slog = logging.getLogger(f"{__name__}.{sample_func.__name__}.{SentimentAnalyzer.__name__}")
                 slog.debug("Selected SentimentAnalyzer: %s", SentimentAnalyzer.__name__)
 
                 for Tokenizer in [
+                    PottsTokenizerWithNegation,
+                    PottsTokenizer,
+                    HuggingBertTokenizer,
                     PlainTokenizer,
                     LowercaseTokenizer,
                     NLTKWordTokenizer,
-                    PottsTokenizer,
-                    PottsTokenizerWithNegation,
                 ]:
 
                     slog = logging.getLogger(f"{__name__}.{sample_func.__name__}.{SentimentAnalyzer.__name__}.{Tokenizer.__name__}")
diff --git a/unimore_bda_6/analysis/nltk_sentiment.py b/unimore_bda_6/analysis/nltk_sentiment.py
index 4c063b7..2f33b1b 100644
--- a/unimore_bda_6/analysis/nltk_sentiment.py
+++ b/unimore_bda_6/analysis/nltk_sentiment.py
@@ -107,7 +107,7 @@ class NLTKSentimentAnalyzer(BaseSentimentAnalyzer):
             raise NotTrainedError()
 
         # Tokenize the input
-        tokens = self.tokenizer.tokenize_plain(text)
+        tokens = self.tokenizer.tokenize_and_split_plain(text)
 
         # Run the classification method
         return self.model.classify(instance=tokens)
diff --git a/unimore_bda_6/analysis/tf_text.py b/unimore_bda_6/analysis/tf_text.py
index e8e8fa9..35cc2d4 100644
--- a/unimore_bda_6/analysis/tf_text.py
+++ b/unimore_bda_6/analysis/tf_text.py
@@ -189,9 +189,11 @@ class TensorflowCategorySentimentAnalyzer(TensorflowSentimentAnalyzer):
                 input_dim=TENSORFLOW_MAX_FEATURES.__wrapped__ + 1,
                 output_dim=TENSORFLOW_EMBEDDING_SIZE.__wrapped__,
             ),
-            tensorflow.keras.layers.Dropout(0.10),
+            tensorflow.keras.layers.Dropout(0.25),
             tensorflow.keras.layers.GlobalAveragePooling1D(),
-            tensorflow.keras.layers.Dropout(0.10),
+            tensorflow.keras.layers.Dropout(0.25),
+            tensorflow.keras.layers.Dense(8),
+            tensorflow.keras.layers.Dropout(0.25),
             tensorflow.keras.layers.Dense(5, activation="softmax"),
         ])
 
@@ -240,18 +242,20 @@ class TensorflowPolarSentimentAnalyzer(TensorflowSentimentAnalyzer):
                 input_dim=TENSORFLOW_MAX_FEATURES.__wrapped__ + 1,
                 output_dim=TENSORFLOW_EMBEDDING_SIZE.__wrapped__,
             ),
-            tensorflow.keras.layers.Dropout(0.10),
+            tensorflow.keras.layers.Dropout(0.25),
             tensorflow.keras.layers.GlobalAveragePooling1D(),
-            tensorflow.keras.layers.Dropout(0.10),
-            tensorflow.keras.layers.Dense(1),
+            tensorflow.keras.layers.Dropout(0.25),
+            tensorflow.keras.layers.Dense(8),
+            tensorflow.keras.layers.Dropout(0.25),
+            tensorflow.keras.layers.Dense(1, activation="relu"),
         ])
 
         log.debug("Compiling model: %s", model)
         model.compile(
-            optimizer=tensorflow.keras.optimizers.Adadelta(global_clipnorm=1.0),
-            loss=tensorflow.keras.losses.MeanSquaredError(),
+            optimizer=tensorflow.keras.optimizers.Adam(clipnorm=2.0),
+            loss=tensorflow.keras.losses.MeanAbsoluteError(),
             metrics=[
-                tensorflow.keras.metrics.MeanAbsoluteError(),
+                # tensorflow.keras.metrics.MeanAbsoluteError(),
             ]
         )
 
@@ -259,7 +263,7 @@ class TensorflowPolarSentimentAnalyzer(TensorflowSentimentAnalyzer):
         return model
 
     def _translate_prediction(self, a: numpy.array) -> Category:
-        return (a[0, 0] + 0.5) * 5
+        return 1 + (a[0, 0] + 0.5) * 4
 
 
 __all__ = (
diff --git a/unimore_bda_6/config.py b/unimore_bda_6/config.py
index c07d29f..3d79f6f 100644
--- a/unimore_bda_6/config.py
+++ b/unimore_bda_6/config.py
@@ -109,10 +109,10 @@ def TENSORFLOW_EMBEDDING_SIZE(val: str | None) -> int:
     """
     The size of the embeddings tensor to use in Tensorflow models.
 
-    Defaults to `6`.
+    Defaults to `12`.
     """
     if val is None:
-        return 6
+        return 12
     try:
         return int(val)
     except ValueError:
@@ -124,10 +124,10 @@ def TENSORFLOW_EPOCHS(val: str | None) -> int:
     """
     The number of epochs to train Tensorflow models for.
 
-    Defaults to `12`.
+    Defaults to `5`.
     """
     if val is None:
-        return 12
+        return 5
     try:
         return int(val)
     except ValueError:
diff --git a/unimore_bda_6/database/datatypes.py b/unimore_bda_6/database/datatypes.py
index f5517f1..fbdd232 100644
--- a/unimore_bda_6/database/datatypes.py
+++ b/unimore_bda_6/database/datatypes.py
@@ -41,7 +41,7 @@ class Review:
         return tensorflow.convert_to_tensor(self.text, dtype=tensorflow.string)
 
     def to_tensor_normvalue(self) -> tensorflow.Tensor:
-        return tensorflow.convert_to_tensor([self.category / 5 - 0.5], dtype=tensorflow.float32)
+        return tensorflow.convert_to_tensor([(self.category - 1) / 4 - 0.5], dtype=tensorflow.float32)
 
     def to_tensor_tuple_normvalue(self) -> tuple[tensorflow.Tensor, tensorflow.Tensor]:
         return (
diff --git a/unimore_bda_6/tokenizer/__init__.py b/unimore_bda_6/tokenizer/__init__.py
index 290c706..a5bcfc7 100644
--- a/unimore_bda_6/tokenizer/__init__.py
+++ b/unimore_bda_6/tokenizer/__init__.py
@@ -7,3 +7,4 @@ from .nltk_word_tokenize import *
 from .potts import *
 from .plain import *
 from .lower import *
+from .hugging import *
diff --git a/unimore_bda_6/tokenizer/base.py b/unimore_bda_6/tokenizer/base.py
index 61349e0..01e8d41 100644
--- a/unimore_bda_6/tokenizer/base.py
+++ b/unimore_bda_6/tokenizer/base.py
@@ -31,16 +31,18 @@ class BaseTokenizer:
         """
         Run `.tokenize_plain`, then split the result using `str.split`.
         """
-        return self.tokenize_plain(text).split()
+        text = self.tokenize_plain(text)
+        text = text.split()
+        return text
 
     @__not_implemented
-    def tokenize_tensorflow(self, text: "tensorflow.Tensor") -> "tensorflow.Tensor":
+    def tokenize_tensorflow(self, text: tensorflow.Tensor) -> tensorflow.Tensor:
         """
         Convert a `tensorflow.Tensor` string into another `tensorflow.Tensor` space-separated string.
         """
         raise NotImplementedError()
 
-    def tokenize_tensorflow_and_expand_dims(self, text: "tensorflow.Tensor") -> "tensorflow.Tensor":
+    def tokenize_tensorflow_and_expand_dims(self, text: tensorflow.Tensor) -> tensorflow.Tensor:
         """
         Run `.tokenize_tensorflow`, then add a dimension to the tensor for reasons unknown to me, but required to get `tensorflow` to work properly.
         """
diff --git a/unimore_bda_6/tokenizer/hugging.py b/unimore_bda_6/tokenizer/hugging.py
new file mode 100644
index 0000000..40cc682
--- /dev/null
+++ b/unimore_bda_6/tokenizer/hugging.py
@@ -0,0 +1,26 @@
+import abc
+import tokenizers
+
+from .base import BaseTokenizer
+
+
+class HuggingTokenizer(BaseTokenizer, metaclass=abc.ABCMeta):
+    def __init__(self):
+        super().__init__()
+        self.hug: tokenizers.Tokenizer = self._build_hugging_tokenizer()
+
+    def _build_hugging_tokenizer(self) -> tokenizers.Tokenizer:
+        raise NotImplementedError()
+
+    def tokenize_plain(self, text: str) -> str:
+        return " ".join(self.hug.encode(text).tokens)
+
+
+class HuggingBertTokenizer(HuggingTokenizer):
+    def _build_hugging_tokenizer(self):
+        return tokenizers.Tokenizer.from_pretrained("bert-base-cased")
+
+
+__all__ = (
+    "HuggingBertTokenizer",
+)
diff --git a/unimore_bda_6/tokenizer/potts.py b/unimore_bda_6/tokenizer/potts.py
index d30c6cb..bfec472 100644
--- a/unimore_bda_6/tokenizer/potts.py
+++ b/unimore_bda_6/tokenizer/potts.py
@@ -16,78 +16,62 @@ class PottsTokenizer(BaseTokenizer):
 
     # noinspection RegExpRepeatedSpace
     # language=pythonregexp
-    emoticon_re_string = r"""
-            [<>]?
-            [:;=8]                   # eyes
-            [\-o*']?                 # optional nose
-            [)\](\[dDpP/:}{@|\\]     # mouth
-            |
-            [)\](\[dDpP/:}{@|\\]     # mouth
-            [\-o*']?                 # optional nose
-            [:;=8]                   # eyes
-            [<>]?
-        """
+    emoticon_re_string = r"""[<>]?[:;=8][\-o*']?[)\](\[dDpP/:}{@|\\]"""
 
-    emoticon_re = re.compile(emoticon_re_string, re.VERBOSE | re.I)
+    emoticon_re = re.compile(emoticon_re_string)
 
-    # noinspection RegExpRepeatedSpace,RegExpUnnecessaryNonCapturingGroup
-    # language=pythonregexp
-    words_re_string = (
+    words_re_string = "(" + "|".join([
         # Emoticons:
         emoticon_re_string
         ,
         # Phone numbers:
-        r"""
-        (?:            # (international)
-            \+?[01]
-            [\-\s.]*
-        )?
-        (?:            # (area code)
-            [(]?
-            \d{3}
-            [\-\s.)]*
-        )?
-        \d{3}          # exchange
-        [\-\s.]*
-        \d{4}          # base
-        """
+        # language=pythonregexp
+        r"""(?:[+]?[01][\s.-]*)?(?:[(]?\d{3}[\s.)-]*)?\d{3}[\-\s.]*\d{4}"""
         ,
         # HTML tags:
+        # language=pythonregexp
         r"""<[^>]+>"""
         ,
         # Twitter username:
+        # language=pythonregexp
         r"""@[\w_]+"""
         ,
         # Twitter hashtags:
-        r"""#+[\w_]+[\w'_\-]*[\w_]+"""
+        # language=pythonregexp
+        r"""#+[\w_]+[\w'_-]*[\w_]+"""
         ,
         # Words with apostrophes or dashes
-        r"""[a-z][a-z'\-_]+[a-z]"""
+        # language=pythonregexp
+        r"""[a-z][a-z'_-]+[a-z]"""
         ,
         # Numbers, including fractions, decimals
-        r"""[+\-]?\d+[,/.:-]\d+[+\-]?"""
+        # language=pythonregexp
+        r"""[+-]?\d+(?:[,/.:-]\d+)?"""
         ,
         # Words without apostrophes or dashes
+        # language=pythonregexp
         r"""[\w_]+"""
         ,
         # Ellipsis dots
-        r"""\.(?:\s*\.)+"""
+        # language=pythonregexp
+        r"""[.](?:\s*[.])+"""
         ,
         # Everything else that isn't whitespace
-        r"""(?:\S)"""
-    )
+        # language=pythonregexp
+        r"""\S+"""
+    ]) + ")"
 
-    words_re = re.compile("|".join(words_re_string), re.VERBOSE | re.I)
+    words_re = re.compile(words_re_string, re.I)
 
     # language=pythonregexp
     digit_re_string = r"&#\d+;"
 
-    digit_re = re.compile(digit_re_string, re.VERBOSE)
+    digit_re = re.compile(digit_re_string)
 
     # language=pythonregexp
     alpha_re_string = r"&\w+;"
 
-    alpha_re = re.compile(alpha_re_string, re.VERBOSE)
+    alpha_re = re.compile(alpha_re_string)
 
     amp = "&amp;"
 
@@ -118,7 +102,7 @@ class PottsTokenizer(BaseTokenizer):
             s = s.replace(cls.amp, " and ")
         return s
 
-    def tokenize_plain(self, text: str) -> t.Iterable[str]:
+    def tokenize_plain(self, text: str) -> str:
         # Fix HTML character entitites
         s = self.__html2string(text)
         # Tokenize
@@ -132,10 +116,10 @@ class PottsTokenizer(BaseTokenizer):
 
 
 class PottsTokenizerWithNegation(PottsTokenizer):
-    def tokenize_plain(self, text: str) -> t.Iterable[str]:
-        words = super().tokenize_plain(text)
+    def tokenize_plain(self, text: str) -> str:
+        words = super().tokenize_plain(text).split()
         nltk.sentiment.util.mark_negation(words, shallow=True)
-        return words
+        return " ".join(words)
 
 
 __all__ = (