2017-10-20 125 views
1

我是新來的機器學習和嘗試TFlearn,因爲它很簡單。Tflearn質量差分類器?

我想做一個基本的分類器,我覺得很有趣。 我的目標是訓練系統來預測一個點在哪個方向。

例如,如果我輸入兩個2D座標(50,50)(51,51),系統必須預測方向是NE(東北)。 如果我喂(50,50)(49,49)系統必須預測方向是SW(西南方)

輸入: X1,Y1,X2,Y2,標籤
輸出: 0〜8對於8方向。

因此,這裏是小的代碼我寫的,

from __future__ import print_function 
import numpy as np 
import tflearn 
import tensorflow as tf 
import time 
from tflearn.data_utils import load_csv 

#Sample input 50,50,51,51,5 
data, labels = load_csv(filename, target_column=4, 
         categorical_labels=True, n_classes=8) 

my_optimizer = tflearn.SGD(learning_rate=0.1) 
net = tflearn.input_data(shape=[None, 4]) 
net = tflearn.fully_connected(net, 32) #input 4, output 32 
net = tflearn.fully_connected(net, 32) #input 32, output 32 
net = tflearn.fully_connected(net, 8, activation='softmax') 
net = tflearn.regression(net,optimizer=my_optimizer) 

model = tflearn.DNN(net) 

model.fit(data, labels, n_epoch=100, batch_size=100000, show_metric=True) 

model.save("direction-classifier.tfl") 

我面對的問題是,即使我通過了約4000萬的輸入樣本,該系統的精度更是低至20%。
我限制了輸入40-x-6040-y-60

我不明白,如果我過裝的樣品,因準確率從未在整個總4000萬倍的投入訓練期間高

爲什麼精度如此低這個簡單的例子?

編輯: 我減少了學習率,並使批量小。但是,結果仍然相同,準確性很差。 我已經包含了前25個步驟的輸出。

-- 
Training Step: 100000 | total loss: 6.33983 | time: 163.327s 
| SGD | epoch: 001 | loss: 6.33983 - acc: 0.0663 -- iter: 999999/999999 
-- 
Training Step: 200000 | total loss: 6.84055 | time: 161.981ss 
| SGD | epoch: 002 | loss: 6.84055 - acc: 0.1568 -- iter: 999999/999999 
-- 
Training Step: 300000 | total loss: 5.90203 | time: 158.853ss 
| SGD | epoch: 003 | loss: 5.90203 - acc: 0.1426 -- iter: 999999/999999 
-- 
Training Step: 400000 | total loss: 5.97782 | time: 157.607ss 
| SGD | epoch: 004 | loss: 5.97782 - acc: 0.1465 -- iter: 999999/999999 
-- 
Training Step: 500000 | total loss: 5.97215 | time: 155.929ss 
| SGD | epoch: 005 | loss: 5.97215 - acc: 0.1234 -- iter: 999999/999999 
-- 
Training Step: 600000 | total loss: 6.86967 | time: 157.299ss 
| SGD | epoch: 006 | loss: 6.86967 - acc: 0.1230 -- iter: 999999/999999 
-- 
Training Step: 700000 | total loss: 6.10330 | time: 158.137ss 
| SGD | epoch: 007 | loss: 6.10330 - acc: 0.1242 -- iter: 999999/999999 
-- 
Training Step: 800000 | total loss: 5.81901 | time: 157.464ss 
| SGD | epoch: 008 | loss: 5.81901 - acc: 0.1464 -- iter: 999999/999999 
-- 
Training Step: 900000 | total loss: 7.09744 | time: 157.486ss 
| SGD | epoch: 009 | loss: 7.09744 - acc: 0.1359 -- iter: 999999/999999 
-- 
Training Step: 1000000 | total loss: 7.19259 | time: 158.369s 
| SGD | epoch: 010 | loss: 7.19259 - acc: 0.1248 -- iter: 999999/999999 
-- 
Training Step: 1100000 | total loss: 5.60177 | time: 157.221ss 
| SGD | epoch: 011 | loss: 5.60177 - acc: 0.1378 -- iter: 999999/999999 
-- 
Training Step: 1200000 | total loss: 7.16676 | time: 158.607ss 
| SGD | epoch: 012 | loss: 7.16676 - acc: 0.1210 -- iter: 999999/999999 
-- 
Training Step: 1300000 | total loss: 6.19163 | time: 163.711ss 
| SGD | epoch: 013 | loss: 6.19163 - acc: 0.1635 -- iter: 999999/999999 
-- 
Training Step: 1400000 | total loss: 7.46101 | time: 162.091ss 
| SGD | epoch: 014 | loss: 7.46101 - acc: 0.1216 -- iter: 999999/999999 
-- 
Training Step: 1500000 | total loss: 7.78055 | time: 158.468ss 
| SGD | epoch: 015 | loss: 7.78055 - acc: 0.1122 -- iter: 999999/999999 
-- 
Training Step: 1600000 | total loss: 6.03101 | time: 158.251ss 
| SGD | epoch: 016 | loss: 6.03101 - acc: 0.1103 -- iter: 999999/999999 
-- 
Training Step: 1700000 | total loss: 5.59769 | time: 158.083ss 
| SGD | epoch: 017 | loss: 5.59769 - acc: 0.1182 -- iter: 999999/999999 
-- 
Training Step: 1800000 | total loss: 5.45591 | time: 158.088ss 
| SGD | epoch: 018 | loss: 5.45591 - acc: 0.0868 -- iter: 999999/999999 
-- 
Training Step: 1900000 | total loss: 6.54951 | time: 157.755ss 
| SGD | epoch: 019 | loss: 6.54951 - acc: 0.1353 -- iter: 999999/999999 
-- 
Training Step: 2000000 | total loss: 6.18566 | time: 157.408ss 
| SGD | epoch: 020 | loss: 6.18566 - acc: 0.0551 -- iter: 999999/999999 
-- 
Training Step: 2100000 | total loss: 4.95146 | time: 157.572ss 
| SGD | epoch: 021 | loss: 4.95146 - acc: 0.1114 -- iter: 999999/999999 
-- 
Training Step: 2200000 | total loss: 5.97208 | time: 157.279ss 
| SGD | epoch: 022 | loss: 5.97208 - acc: 0.1277 -- iter: 999999/999999 
-- 
Training Step: 2300000 | total loss: 6.75645 | time: 157.201ss 
| SGD | epoch: 023 | loss: 6.75645 - acc: 0.1507 -- iter: 999999/999999 
-- 
Training Step: 2400000 | total loss: 7.04119 | time: 157.346ss 
| SGD | epoch: 024 | loss: 7.04119 - acc: 0.1512 -- iter: 999999/999999 
-- 
Training Step: 2500000 | total loss: 5.95451 | time: 157.722ss 
| SGD | epoch: 025 | loss: 5.95451 - acc: 0.1421 -- iter: 999999/999999 
+0

包含多個時期的損失函數可能會有幫助。它是否穩步下降?或者它在振盪?有幾件事要嘗試(如果你還沒有的話):減少隱藏層的數量。減少批量大小。降低學習率。 – nickandross

+0

@nickandross根據要求進行更改幷包含數據。可悲的是,結果依然如此。 – SamwellTarly

+0

看起來損失並沒有穩步下降。數據中可能存在問題?我對TFlearn不熟悉,但是我使用[我自己的ANN類](https://github.com/nicholastoddsmith/pythonml/blob/master/TFANN.py)(與TFlearn類似)重現了這個問題,而我是能夠獲得> 90%的準確度。如果您有興趣,我可以發佈我的代碼。 – nickandross

回答

1

匝優化器導致了所有問題。當自定義優化器被刪除時,損失開始正確下降,準確度提高到99%

必須修改以下兩行。

my_optimizer = tflearn.SGD(learning_rate=0.1) 
net = tflearn.regression(net,optimizer=my_optimizer) 

net = tflearn.regression(net) 

取得了完美的效果所取代。

+0

請選擇此答案作爲最後一個完成正在進行的線程。 – ye9ane

1

如在我的上述評論所討論的,這裏是代碼,使用a MLP helper class I created訓練一個多層感知分類器模型。該課程使用TensorFlow實施,並遵循scikit-learn fit,predict,score界面。

其基本思想是生成一個隨機的開始和結束點,然後使用字典來創建基於方向的標籤。我使用np.unique來查找生成數據中類標籤的數量,因爲它可能會有所不同(某些方向可能會丟失)。當開始點和結束點相同時,我還包含一個空字符串標籤。

代碼

使用下面的代碼,我能夠在某些運行實現100%的交叉驗證準確性。 進口numpy的從進口sklearn.model_selection NP 從TFANN進口MLPC ShuffleSplit

#Dictionary to lookup direction() 
DM = {(-1, -1):'SW', (-1, 0):'W', (-1, 1):'NW', (0, 1):'N', 
     (1, 1):'NE', (1, 0):'E', (1, -1):'SE', (0, -1):'S', 
     (0, 0):''} 

NR = 4096  #Number of rows in sample matrix 
A1 = np.random.randint(40, 61, size = (NR, 2))  #Random starting point 
A2 = np.random.randint(40, 61, size = (NR, 2))  #Random ending point 
A = np.hstack([A1, A2])   #Concat start and end point as feature vector 
#Create label from direction vector 
Y = np.array([DM[(x, y)] for x, y in (A2 - A1).clip(-1, 1)]) 
NC = len(np.unique(Y))   #Number of classes 
ss = ShuffleSplit(n_splits = 1) 
trn, tst = next(ss.split(A)) #Make a train/test split for cross-validation 
#%% Create and train Multi-Layer Perceptron for Classification (MLPC) 
l = [4, 6, 6, NC]  #Neuron counts in each layer 
mlpc = MLPC(l, batchSize = 64, maxIter = 128, verbose = True) 
mlpc.fit(A[trn], Y[trn]) 
s1 = mlpc.score(A[trn], Y[trn])  #Training accuracy 
s2 = mlpc.score(A[tst], Y[tst])  #Testing accuracy 
s3 = mlpc.score(A, Y)    #Total accuracy 
print('Trn: {:05f}\tTst: {:05f}\tAll: {:05f}'.format(s1, s2, s3)) 

結果

這是我的機器上的上面的代碼的運行示例:

Iter  1   2.59423236 (Batch Size: 64) 
Iter  2   2.25392553 (Batch Size: 64) 
Iter  3   2.02569708 (Batch Size: 64) 
... 
Iter 12   1.53575111 (Batch Size: 64) 
Iter 13   1.47963311 (Batch Size: 64) 
Iter 14   1.42776408 (Batch Size: 64) 
... 
Iter 83   0.23911642 (Batch Size: 64) 
Iter 84   0.22893350 (Batch Size: 64) 
Iter 85   0.23644384 (Batch Size: 64) 
... 
Iter 94   0.21170238 (Batch Size: 64) 
Iter 95   0.20718799 (Batch Size: 64) 
Iter 96   0.21230888 (Batch Size: 64) 
... 
Iter 126   0.17334313 (Batch Size: 64) 
Iter 127   0.16970796 (Batch Size: 64) 
Iter 128   0.15931854 (Batch Size: 64) 
Trn: 0.995659 Tst: 1.000000 All: 0.996094