Holdout set¶

---

This example shows when and how to use ATOM's holdout set in an exploration pipeline.

The data used is a variation on the Australian weather dataset from Kaggle. You can download it from here. The goal of this dataset is to predict whether or not it will rain tomorrow training a binary classifier on target RainTomorrow.

Load the data¶

In [1]:

# Import packages
import pandas as pd
from atom import ATOMClassifier

# Import packages import pandas as pd from atom import ATOMClassifier

In [2]:

# Load data
X = pd.read_csv("./datasets/weatherAUS.csv")

# Let's have a look
X.head()

# Load data X = pd.read_csv("./datasets/weatherAUS.csv") # Let's have a look X.head()

Out[2]:

	Location	MinTemp	MaxTemp	Rainfall	Evaporation	Sunshine	WindGustDir	WindGustSpeed	WindDir9am	WindDir3pm	...	Humidity9am	Humidity3pm	Pressure9am	Pressure3pm	Cloud9am	Cloud3pm	Temp9am	Temp3pm	RainToday	RainTomorrow
0	MelbourneAirport	18.0	26.9	21.4	7.0	8.9	SSE	41.0	W	SSE	...	95.0	54.0	1019.5	1017.0	8.0	5.0	18.5	26.0	Yes	0
1	Adelaide	17.2	23.4	0.0	NaN	NaN	S	41.0	S	WSW	...	59.0	36.0	1015.7	1015.7	NaN	NaN	17.7	21.9	No	0
2	Cairns	18.6	24.6	7.4	3.0	6.1	SSE	54.0	SSE	SE	...	78.0	57.0	1018.7	1016.6	3.0	3.0	20.8	24.1	Yes	0
3	Portland	13.6	16.8	4.2	1.2	0.0	ESE	39.0	ESE	ESE	...	76.0	74.0	1021.4	1020.5	7.0	8.0	15.6	16.0	Yes	1
4	Walpole	16.4	19.9	0.0	NaN	NaN	SE	44.0	SE	SE	...	78.0	70.0	1019.4	1018.9	NaN	NaN	17.4	18.1	No	0

5 rows × 22 columns

Run the pipeline¶

In [3]:

# Initialize atom specifying a fraction of the dataset for holdout
atom = ATOMClassifier(X, n_rows=0.5, holdout_size=0.2, verbose=2, warnings=False)

# Initialize atom specifying a fraction of the dataset for holdout atom = ATOMClassifier(X, n_rows=0.5, holdout_size=0.2, verbose=2, warnings=False)

<< ================== ATOM ================== >>
Algorithm task: binary classification.

Dataset stats ==================== >>
Shape: (56877, 22)
Memory: 24.67 MB
Scaled: False
Missing values: 127079 (10.2%)
Categorical features: 5 (23.8%)
Duplicate samples: 18 (0.0%)
-------------------------------------
Train set size: 42658
Test set size: 14219
Holdout set size: 14219
-------------------------------------
|   |       dataset |         train |          test |
| - | ------------- | ------------- | ------------- |
| 0 |   44113 (3.5) |   33085 (3.5) |   11028 (3.5) |
| 1 |   12764 (1.0) |    9573 (1.0) |    3191 (1.0) |

In [4]:

# The test and holdout fractions are split after subsampling the dataset
# Also note that the holdout data set is not a part of atom's dataset
print("Length loaded data:", len(X))
print("Length dataset + holdout:", len(atom.dataset) + len(atom.holdout))

# The test and holdout fractions are split after subsampling the dataset # Also note that the holdout data set is not a part of atom's dataset print("Length loaded data:", len(X)) print("Length dataset + holdout:", len(atom.dataset) + len(atom.holdout))

Length loaded data: 142193
Length dataset + holdout: 71096

In [5]:

atom.impute()
atom.encode()

atom.impute() atom.encode()

Fitting Imputer...
Imputing missing values...
 --> Dropping 245 samples due to missing values in feature MinTemp.
 --> Dropping 140 samples due to missing values in feature MaxTemp.
 --> Dropping 606 samples due to missing values in feature Rainfall.
 --> Dropping 24376 samples due to missing values in feature Evaporation.
 --> Dropping 27135 samples due to missing values in feature Sunshine.
 --> Dropping 3774 samples due to missing values in feature WindGustDir.
 --> Dropping 3747 samples due to missing values in feature WindGustSpeed.
 --> Dropping 4105 samples due to missing values in feature WindDir9am.
 --> Dropping 1560 samples due to missing values in feature WindDir3pm.
 --> Dropping 533 samples due to missing values in feature WindSpeed9am.
 --> Dropping 1059 samples due to missing values in feature WindSpeed3pm.
 --> Dropping 700 samples due to missing values in feature Humidity9am.
 --> Dropping 1457 samples due to missing values in feature Humidity3pm.
 --> Dropping 5598 samples due to missing values in feature Pressure9am.
 --> Dropping 5597 samples due to missing values in feature Pressure3pm.
 --> Dropping 21546 samples due to missing values in feature Cloud9am.
 --> Dropping 22843 samples due to missing values in feature Cloud3pm.
 --> Dropping 349 samples due to missing values in feature Temp9am.
 --> Dropping 1103 samples due to missing values in feature Temp3pm.
 --> Dropping 606 samples due to missing values in feature RainToday.
Fitting Encoder...
Encoding categorical columns...
 --> LeaveOneOut-encoding feature Location. Contains 26 classes.
 --> LeaveOneOut-encoding feature WindGustDir. Contains 16 classes.
 --> LeaveOneOut-encoding feature WindDir9am. Contains 16 classes.
 --> LeaveOneOut-encoding feature WindDir3pm. Contains 16 classes.
 --> Ordinal-encoding feature RainToday. Contains 2 classes.

In [6]:

# Unlike train and test, the holdout data set is not transformed until used for predictions
atom.holdout

# Unlike train and test, the holdout data set is not transformed until used for predictions atom.holdout

Out[6]:

	Location	MinTemp	MaxTemp	Rainfall	Evaporation	Sunshine	WindGustDir	WindGustSpeed	WindDir9am	WindDir3pm	...	Humidity9am	Humidity3pm	Pressure9am	Pressure3pm	Cloud9am	Cloud3pm	Temp9am	Temp3pm	RainToday	RainTomorrow
0	PearceRAAF	14.0	25.4	0.0	NaN	6.7	N	50.0	NE	W	...	30.0	24.0	1010.5	1008.4	2.0	7.0	19.0	23.8	No	0
1	Witchcliffe	6.5	15.8	4.4	NaN	NaN	W	26.0	NaN	W	...	99.0	58.0	1022.6	1021.3	NaN	NaN	10.1	14.2	Yes	1
2	Adelaide	6.8	18.4	NaN	NaN	NaN	WNW	31.0	SE	WSW	...	49.0	43.0	1023.8	1020.2	NaN	NaN	13.8	18.0	NaN	0
3	Penrith	16.1	28.2	0.0	NaN	NaN	ESE	22.0	NaN	SE	...	73.0	48.0	NaN	NaN	NaN	NaN	21.8	27.7	No	0
4	Cairns	21.7	32.6	0.0	8.0	7.2	SE	33.0	SSE	ESE	...	70.0	50.0	1008.3	1005.5	6.0	7.0	27.2	31.7	No	0
...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...	...
14214	Uluru	13.8	32.6	0.0	NaN	NaN	ENE	43.0	ENE	SSE	...	18.0	8.0	1018.5	1013.2	NaN	NaN	23.5	31.0	No	0
14215	Nuriootpa	15.0	31.6	3.6	6.9	11.2	SW	44.0	ENE	W	...	73.0	23.0	1004.3	1001.9	3.0	NaN	19.8	30.8	Yes	0
14216	WaggaWagga	7.3	12.2	4.6	1.4	0.1	W	48.0	WNW	WNW	...	91.0	85.0	1012.9	1013.3	8.0	7.0	9.8	11.8	Yes	0
14217	Richmond	17.7	32.0	21.4	11.6	NaN	W	39.0	N	W	...	67.0	34.0	1011.0	1008.2	NaN	NaN	23.4	31.4	Yes	0
14218	Katherine	NaN	36.5	NaN	NaN	NaN	ESE	50.0	WNW	SE	...	NaN	83.0	1009.8	1005.8	NaN	5.0	NaN	35.0	NaN	1

14219 rows × 22 columns

In [7]:

atom.run(models=["GNB", "LR", "RF"])

atom.run(models=["GNB", "LR", "RF"])

Training ========================= >>
Models: GNB, LR, RF
Metric: f1


Results for Gaussian Naive Bayes:
Fit ---------------------------------------------
Train evaluation --> f1: 0.6017
Test evaluation --> f1: 0.5981
Time elapsed: 0.034s
-------------------------------------------------
Total time: 0.035s


Results for Logistic Regression:
Fit ---------------------------------------------
Train evaluation --> f1: 0.6182
Test evaluation --> f1: 0.6217
Time elapsed: 0.130s
-------------------------------------------------
Total time: 0.130s


Results for Random Forest:
Fit ---------------------------------------------
Train evaluation --> f1: 1.0
Test evaluation --> f1: 0.6289
Time elapsed: 2.742s
-------------------------------------------------
Total time: 2.742s


Final results ==================== >>
Duration: 2.908s
-------------------------------------
Gaussian Naive Bayes --> f1: 0.5981
Logistic Regression  --> f1: 0.6217
Random Forest        --> f1: 0.6289 ~ !

In [8]:

atom.plot_prc()

atom.plot_prc()

In [9]:

# Based on the results on the test set, we select the best model for further tuning
atom.run("lr_tuned", n_calls=10, n_initial_points=5)

# Based on the results on the test set, we select the best model for further tuning atom.run("lr_tuned", n_calls=10, n_initial_points=5)

Training ========================= >>
Models: LR_tuned
Metric: f1


Running BO for Logistic Regression...
| call             | penalty |       C |  solver | max_iter | l1_ratio |      f1 | best_f1 |    time | total_time |
| ---------------- | ------- | ------- | ------- | -------- | -------- | ------- | ------- | ------- | ---------- |
| Initial point 1  |      l2 | 77.7558 | libli.. |      188 |      --- |  0.6235 |  0.6235 |  0.273s |     0.286s |
| Initial point 2  |      l2 | 21.4645 |    saga |      376 |      --- |  0.6358 |  0.6358 |  0.504s |     0.996s |
| Initial point 3  |      l2 |  7.4023 |   lbfgs |      467 |      --- |  0.6133 |  0.6358 |  0.288s |     1.355s |
| Initial point 4  |      l2 |  0.8242 |   lbfgs |      207 |      --- |   0.613 |  0.6358 |  0.285s |     1.709s |
| Initial point 5  |    none |     --- |   lbfgs |      303 |      --- |  0.6468 |  0.6468 |  0.276s |     2.054s |
| Iteration 6      |    none |     --- | newto.. |      224 |      --- |  0.5964 |  0.6468 |  0.286s |     2.671s |
| Iteration 7      |      l2 | 12.8667 |   lbfgs |      548 |      --- |  0.5628 |  0.6468 |  0.284s |     3.252s |
| Iteration 8      | elast.. |   24.99 |    saga |      527 |      0.3 |  0.6083 |  0.6468 |  0.551s |     4.125s |
| Iteration 9      |      l2 |  0.2174 |     sag |      132 |      --- |  0.6166 |  0.6468 |  0.321s |     4.871s |
| Iteration 10     |    none |     --- |     sag |      556 |      --- |  0.5972 |  0.6468 |  0.363s |     5.526s |
Bayesian Optimization ---------------------------
Best call --> Initial point 5
Best parameters --> {'penalty': 'none', 'solver': 'lbfgs', 'max_iter': 303}
Best evaluation --> f1: 0.6468
Time elapsed: 5.874s
Fit ---------------------------------------------
Train evaluation --> f1: 0.6188
Test evaluation --> f1: 0.6215
Time elapsed: 0.120s
-------------------------------------------------
Total time: 5.995s


Final results ==================== >>
Duration: 5.996s
-------------------------------------
Logistic Regression --> f1: 0.6215

Analyze the results¶

We already used the test set to choose the best model for futher tuning, so this set is no longer truly independent. Although it may not be directly visible in the results, using the test set now to evaluate the tuned LR model would be a mistake, since it carries a bias. For this reason, we have set apart an extra, indepedent set to validate the final model: the holdout set. If we are not going to use the test set for validation, we might as well use it to train the model and so optimize the use of the available data. Use the full_train method for this.

In [10]:

# Re-train the model on the full dataset (train + test) 
atom.lr_tuned.full_train()

# Re-train the model on the full dataset (train + test) atom.lr_tuned.full_train()

Model LR_tuned successfully retrained.

In [11]:

# Evaluate on the holdout set
atom.lr_tuned.evaluate(dataset="holdout")

# Evaluate on the holdout set atom.lr_tuned.evaluate(dataset="holdout")

Out[11]:

accuracy             0.850515
average_precision    0.724313
balanced_accuracy    0.738124
f1                   0.616157
jaccard              0.445251
matthews_corrcoef    0.535804
precision            0.728155
recall               0.534019
roc_auc              0.887911
Name: LR_tuned, dtype: float64

In [12]:

atom.lr_tuned.plot_prc(dataset="holdout")

atom.lr_tuned.plot_prc(dataset="holdout")