Due to recent updates, all users are required to create an Altair One account to login to the RapidMiner community. Click the Register button to create your account using the same email that you have previously used to login to the RapidMiner community. This will ensure that any previously created content will be synced to your Altair One account. Once you login, you will be asked to provide a username that identifies you to other Community users. Email us at Community with questions.
Low pass filter
Learner IBest Answer
-
David_A
Administrator, Moderator, Employee, RMResearcher, Member Posts: 297 
RM Research
Hi @suyash12,exponential smoothing is often used as a low-pass filter.There is a ready to use operator with the same name under Modelling -> Time Series -> Transformation -> Exponential SmoothingA lower value in alpha leads to stronger filtering, as shown in the example below.Best,
David<?xml version="1.0" encoding="UTF-8"?><process version="9.3.001"><br> <context><br> <input/><br> <output/><br> <macros/><br> </context><br> <operator activated="true" class="process" compatibility="9.3.001" expanded="true" name="Process" origin="GENERATED_TUTORIAL"><br> <parameter key="logverbosity" value="init"/><br> <parameter key="random_seed" value="2001"/><br> <parameter key="send_mail" value="never"/><br> <parameter key="notification_email" value=""/><br> <parameter key="process_duration_for_mail" value="30"/><br> <parameter key="encoding" value="SYSTEM"/><br> <process expanded="true"><br> <operator activated="true" class="retrieve" compatibility="9.3.001" expanded="true" height="68" name="Retrieve Monthly Milk Production" origin="GENERATED_TUTORIAL" width="90" x="45" y="34"><br> <parameter key="repository_entry" value="//Samples/Time Series/data sets/Monthly Milk Production"/><br> </operator><br> <operator activated="true" class="time_series:exponential_smoothing" compatibility="9.3.001" expanded="true" height="68" name="Exponential Smoothing" origin="GENERATED_TUTORIAL" width="90" x="246" y="34"><br> <parameter key="attribute_filter_type" value="single"/><br> <parameter key="attribute" value="Monthly milk production / pounds per cow"/><br> <parameter key="attributes" value=""/><br> <parameter key="use_except_expression" value="false"/><br> <parameter key="value_type" value="numeric"/><br> <parameter key="use_value_type_exception" value="false"/><br> <parameter key="except_value_type" value="real"/><br> <parameter key="block_type" value="value_series"/><br> <parameter key="use_block_type_exception" value="false"/><br> <parameter key="except_block_type" value="value_series_end"/><br> <parameter key="invert_selection" value="false"/><br> <parameter key="include_special_attributes" value="false"/><br> <parameter key="overwrite_attributes" value="false"/><br> <parameter key="new_attributes_postfix" value="_smoothed_alpha_0.8"/><br> <parameter key="alpha" value="0.8"/><br> <description align="center" color="gray" colored="true" width="126">alpha = 0.8</description><br> </operator><br> <operator activated="true" class="time_series:exponential_smoothing" compatibility="9.3.001" expanded="true" height="68" name="Exponential Smoothing (2)" origin="GENERATED_TUTORIAL" width="90" x="447" y="34"><br> <parameter key="attribute_filter_type" value="single"/><br> <parameter key="attribute" value="Monthly milk production / pounds per cow"/><br> <parameter key="attributes" value=""/><br> <parameter key="use_except_expression" value="false"/><br> <parameter key="value_type" value="numeric"/><br> <parameter key="use_value_type_exception" value="false"/><br> <parameter key="except_value_type" value="real"/><br> <parameter key="block_type" value="value_series"/><br> <parameter key="use_block_type_exception" value="false"/><br> <parameter key="except_block_type" value="value_series_end"/><br> <parameter key="invert_selection" value="false"/><br> <parameter key="include_special_attributes" value="false"/><br> <parameter key="overwrite_attributes" value="false"/><br> <parameter key="new_attributes_postfix" value="_smoothed_alpha_0.5"/><br> <parameter key="alpha" value="0.5"/><br> <description align="center" color="gray" colored="true" width="126">alpha = 0.5</description><br> </operator><br> <operator activated="true" class="time_series:exponential_smoothing" compatibility="9.3.001" expanded="true" height="68" name="Exponential Smoothing (3)" origin="GENERATED_TUTORIAL" width="90" x="648" y="34"><br> <parameter key="attribute_filter_type" value="single"/><br> <parameter key="attribute" value="Monthly milk production / pounds per cow"/><br> <parameter key="attributes" value=""/><br> <parameter key="use_except_expression" value="false"/><br> <parameter key="value_type" value="numeric"/><br> <parameter key="use_value_type_exception" value="false"/><br> <parameter key="except_value_type" value="real"/><br> <parameter key="block_type" value="value_series"/><br> <parameter key="use_block_type_exception" value="false"/><br> <parameter key="except_block_type" value="value_series_end"/><br> <parameter key="invert_selection" value="false"/><br> <parameter key="include_special_attributes" value="false"/><br> <parameter key="overwrite_attributes" value="false"/><br> <parameter key="new_attributes_postfix" value="_smoothed_alpha_0.1"/><br> <parameter key="alpha" value="0.1"/><br> <description align="center" color="gray" colored="true" width="126">alpha = 0.1</description><br> </operator><br> <connect from_op="Retrieve Monthly Milk Production" from_port="output" to_op="Exponential Smoothing" to_port="example set"/><br> <connect from_op="Exponential Smoothing" from_port="example set" to_op="Exponential Smoothing (2)" to_port="example set"/><br> <connect from_op="Exponential Smoothing (2)" from_port="example set" to_op="Exponential Smoothing (3)" to_port="example set"/><br> <connect from_op="Exponential Smoothing (3)" from_port="example set" to_port="result 1"/><br> <portSpacing port="source_input 1" spacing="0"/><br> <portSpacing port="sink_result 1" spacing="0"/><br> <portSpacing port="sink_result 2" spacing="0"/><br> <description align="center" color="green" colored="true" height="320" resized="true" width="565" x="210" y="12"><br> <br> <br> <br> <br> <br> <br> <br> <br> Compare the effect of the smoothing factor alpha:<br><br>alpha = 0.8 : very little smoothing<br><br>alpha = 0.5 : some smoothing, but the pattern is still visible<br><br>alpha = 0.1 : the series peaks are drasticly reduced</description><br> </process><br> </operator><br></process><br><br>
5
Answers
MarlaBot