Tensorflow structured data model.predict() returns incorrect probabilities - python-3.x

Question

I'm trying to follow a Tensorflow tutorial (i'm a beginner) for structured data models with some changes along the way.
My purpose is to create a model to which i provide data (in csv format) that looks something like this (the example has only 2 features but i want to extend it after i figure it out):
power_0,power_1,result
0.2,0.3,draw
0.8,0.1,win
0.3,0.1,draw
0.7,0.2,win
0.0,0.4,lose
I created the model using the following code:
def get_labels(df, label, mapping):
raw_y_true = df.pop(label)
y_true = np.zeros((len(raw_y_true)))
for i, raw_label in enumerate(raw_y_true):
y_true[i] = mapping[raw_label]
return y_true
tf.compat.v1.enable_eager_execution()
mapping_to_numbers = {'win': 0, 'draw': 1, 'lose': 2}
data_frame = pd.read_csv('data.csv')
data_frame.head()
train, test = train_test_split(data_frame, test_size=0.2)
train, val = train_test_split(train, test_size=0.2)
train_labels = np.array(get_labels(train, label='result', mapping=mapping_to_numbers))
val_labels = np.array(get_labels(val, label='result', mapping=mapping_to_numbers))
test_labels = np.array(get_labels(test, label='result', mapping=mapping_to_numbers))
train_features = np.array(train)
val_features = np.array(val)
test_features = np.array(test)
model = tf.keras.Sequential([
tf.keras.layers.Dense(128, activation='relu', input_shape=(train_features.shape[-1],)),
tf.keras.layers.Dense(128, activation='relu'),
tf.keras.layers.Dropout(0.3),
tf.keras.layers.Dense(128, activation='relu'),
tf.keras.layers.Dropout(0.3),
tf.keras.layers.Dense(3, activation='sigmoid'),
])
model.compile(
optimizer='adam',
loss='binary_crossentropy',
metrics=['accuracy'],
run_eagerly=True)
epochs = 10
batch_size = 100
history = model.fit(
train_features,
train_labels,
epochs=epochs,
validation_data=(val_features, val_labels))
input_data_frame = pd.read_csv('input.csv')
input_data_frame.head()
input_data = np.array(input_data_frame)
print(model.predict(input_data))
input.csv looks as following:
power_0,power_1
0.8,0.1
0.7,0.2
And the actual result is:
[[0.00604381 0.00242573 0.00440606]
[0.01321151 0.00634229 0.01041476]]
I expected to get the probability for each label ('win', 'draw' and 'lose'), can anyone please help me with this?
Thanks in advance

Answer 1

Use softmax activation in this line tf.keras.layers.Dense(3, activation='sigmoid').

Answer 2

This works well for me with your example:
model = tf.keras.Sequential([
tf.keras.layers.Flatten(input_shape=(train_features.shape[-1],)),
tf.keras.layers.Dense(128, activation='relu'),
tf.keras.layers.Dense(16, activation='relu'),
tf.keras.layers.Dense(3, activation='softmax'),
])
model.compile(
optimizer='adam',
loss='sparse_categorical_crossentropy',
metrics=['accuracy'],
run_eagerly=True)
Using Flatten Layer

Answer 3

I have to write my suggestions here because i cant comment yet.
#zihaozhihao is right you have to use softmax instead of sigmoid because you dont work with a binary problem. Another problem might be your loss function which is:
model.compile(
optimizer='adam',
loss='binary_crossentropy',
metrics=['accuracy'],
run_eagerly=True)
Try to use loss='categorical_crossentropy',because you are working with a multilabel classification. You could read more about multilable classification here and here.
As for your propability question. You get the propability of each class for your two test inputs.For example:
win draw loss
[[0.00604381 0.00242573 0.00440606]
[0.01321151 0.00634229 0.01041476]]
The Problem is your loss function and the activation function which leads to strange propability values. You might want to check this post here for more information.
Hope this helps a little and feel free to ask.

Answer 4

Since it is a multiclass classification problem, please use categorical_crossentropy instead of binary_crossentropy for loss function, also use softmax instead of sigmoid as activation function.
Also, you should increase your epochs for getting better convergence.