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- GLMPredictPerSegment(newdata=None, object=None, id_column=None, accumulate=None, output_prob=False, output_responses=None, partition_column=None, **generic_arguments)
- DESCRIPTION:
The GLMPredictPerSegment() function uses the model generated by
the GLMPerSegment() function to predict target values (regression)
and class labels (classification) on new input data.
Notes:
* All input features must be numeric. The categorical columns should be converted
to numerical columns as preprocessing step, such as using the following functions:
* OneHotEncodingFit() and OneHotEncodingTransform().
* OrdinalEncodingFit() and OrdinalEncodingTransform().
* TargetEncodingFit() and TargetEncodingTransform().
The OneHotEncodingFit() and OneHotEncodingTransform() functions support segment
functions. However, the OrdinalEncodingFit() and OrdinalEncodingTransform(),
TargetEncodingFit() and TargetEncodingTransform() functions do not support segment
functions. You must run these functions one-by-one on each partition.
* The preprocessing steps carried out for GLMPerSegment() should be done for
the test data set as well before prediction.
* Prediction accuracy metrics such as MSE, precision, recall, ROC are not
generated by the function. The user should use RegressionEvaluator(),
ClassificationEvaluator() and ROC() functions as post-processing steps.
These functions do not support segment functions and the workaround is to run
these functions one by one on each partition.
* Any observation with missing value in an input column is ignored and it shows
in the output with specific error code. User can use some imputation function,
such as SimpleImputeFit() and SimpleImputeTransform() to do imputation or filling
of missing values.
PARAMETERS:
newdata:
Required Argument.
Specifies the teradataml DataFrame containing the input data.
Types: teradataml DataFrame
object:
Required Argument.
Specifies the teradataml DataFrame containing the model data
generated by GLMPerSegment() function or an instance of GLMPerSegment.
Types: teradataml DataFrame or GLMPerSegment
id_column:
Required Argument.
Specifies the input data column name that uniquely
identifies an observation in the input data.
Types: str
accumulate:
Optional Argument.
Specifies the name(s) of input teradataml DataFrame column(s) to copy to the
output.
Types: str OR list of Strings (str)
output_prob:
Optional Argument.
Specifies whether function should output the probability for each response.
Default Value: False
Types: bool
output_responses:
Optional Argument.
Specifies the class labels for output probabilities. A label must be 0 or 1.
If not specified, then the function outputs the probability of the predicted response.
Note:
* The "output_responses" argument works only when "output_prob"
is True.
Types: str OR list of Strings (str)
partition_column:
Optional Argument.
Specifies the name of the "input_data" columns on which to partition the input.
The name should be consistent with the "data_partition_column" name. If the
"data_partition_column" is unicode with foreign language characters, then it is
necessary to specify "partition_column" argument.
Types: str
**generic_arguments:
Specifies the generic keyword arguments SQLE functions accept. Below
are the generic keyword arguments:
persist:
Optional Argument.
Specifies whether to persist the results of the
function in a table or not. When set to True,
results are persisted in a table; otherwise,
results are garbage collected at the end of the
session.
Default Value: False
Types: bool
volatile:
Optional Argument.
Specifies whether to put the results of the
function in a volatile table or not. When set to
True, results are stored in a volatile table,
otherwise not.
Default Value: False
Types: bool
Function allows the user to partition, hash, order or local
order the input data. These generic arguments are available
for each argument that accepts teradataml DataFrame as
input and can be accessed as:
* "<input_data_arg_name>_partition_column" accepts str or
list of str (Strings)
* "<input_data_arg_name>_hash_column" accepts str or list
of str (Strings)
* "<input_data_arg_name>_order_column" accepts str or list
of str (Strings)
* "local_order_<input_data_arg_name>" accepts boolean
Note:
These generic arguments are supported by teradataml if
the underlying SQLE Engine function supports, else an
exception is raised.
RETURNS:
Instance of GLMPredictPerSegment.
Output teradataml DataFrames can be accessed using attribute
references, such as GLMPredictPerSegmentObj.<attribute_name>.
Output teradataml DataFrame attribute name is:
result
RAISES:
TeradataMlException, TypeError, ValueError
EXAMPLES:
# Notes:
# 1. Get the connection to Vantage to execute the function.
# 2. One must import the required functions mentioned in
# the example from teradataml.
# 3. Function will raise error if not supported on the Vantage
# user is connected to.
# Load the example data.
load_example_data("decisionforestpredict", ["housing_train", "housing_test"])
# Create teradataml DataFrame objects.
housing_train = DataFrame.from_table("housing_train")
housing_test = DataFrame.from_table("housing_test")
# Check the list of available analytic functions.
display_analytic_functions()
# Filter the rows from train dataset with homestyle as Classic and Eclectic.
binomial_housing_train = DataFrame('housing_train', index_label="homestyle")
binomial_housing_train = binomial_housing_train.filter(like = 'ic', axis = 'rows')
binomial_housing_test = DataFrame('housing_test', index_label="homestyle")
binomial_housing_test = binomial_housing_test.filter(like = 'ic', axis = 'rows')
# GLMPerSegment() function requires features in numeric format for processing,
# so dropping the non-numeric columns.
binomial_housing_train = binomial_housing_train.drop(columns=["driveway", "recroom",
"gashw", "airco", "prefarea",
"fullbase"])
gaussian_housing_train = binomial_housing_train.drop(columns="homestyle")
binomial_housing_test = binomial_housing_test.drop(columns=["driveway", "recroom",
"gashw", "airco", "prefarea",
"fullbase"])
gaussian_housing_test = binomial_housing_test.drop(columns="homestyle")
# Transform the train dataset categorical values to encoded values.
housing_train_ordinal_encodingfit = OrdinalEncodingFit(
target_column='homestyle',
data=binomial_housing_train)
housing_train_ordinal_encodingtransform = OrdinalEncodingTransform(
data=binomial_housing_train,
object=housing_train_ordinal_encodingfit.result,
accumulate=["sn", "price", "lotsize",
"bedrooms", "bathrms", "stories"])
housing_test_ordinal_encodingfit = OrdinalEncodingFit(
target_column='homestyle',
data=binomial_housing_test)
housing_test_ordinal_encodingtransform = OrdinalEncodingTransform(
data=binomial_housing_test,
object=housing_test_ordinal_encodingfit.result,
accumulate=["sn", "price", "lotsize",
"bedrooms", "bathrms", "stories"])
# Example 1: Train the model using the 'Gaussian' family.
# Predict the price using GLMPredictPerSegment().
# Train the model using the 'Gaussian' family.
GLMPerSegment_out_1 = GLMPerSegment(data=gaussian_housing_train,
data_partition_column="stories",
input_columns=['garagepl', 'lotsize', 'bedrooms', 'bathrms'],
response_column="price",
family="Gaussian",
iter_max=1000,
batch_size=9)
# Predict the price using GLMPredictPerSegment().
GLMPredictPerSegment_out_1 = GLMPredictPerSegment(newdata=gaussian_housing_test,
newdata_partition_column="stories",
object=GLMPerSegment_out_1,
object_partition_column="stories",
id_column="sn")
# Print the result DataFrame.
print(GLMPredictPerSegment_out_1.result)
# Example 2: Train the model using the 'Binomial' family.
# Predict the homestyle using GLMPredictPerSegment().
# Train the model using the 'Binomial' family.
GLMPerSegment_out_2 = GLMPerSegment(data=housing_train_ordinal_encodingtransform.result,
data_partition_column="stories",
input_columns=['price', 'lotsize', 'bedrooms', 'bathrms'],
response_column="homestyle",
family="Binomial",
iter_max=100)
# Predict the homestyle using GLMPredictPerSegment().
GLMPredictPerSegment_out_2 = GLMPredictPerSegment(
newdata=housing_test_ordinal_encodingtransform.result,
newdata_partition_column="stories",
object=GLMPerSegment_out_2,
object_partition_column="stories",
id_column="sn",
output_prob=True,
output_responses=["0", "1"]
)
# Print the result DataFrame.
print(GLMPredictPerSegment_out_2.result)
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