Java 类名:com.alibaba.alink.operator.batch.timeseries.AutoGarchBatchOp
Python 类名:AutoGarchBatchOp
功能介绍
给定分组,对每一组的数据使用AutoGarch进行时间序列预测。
算法原理
garch(Generalized AutoRegressive Conditional Heteroskedasticity) 又称广义自回归条件异方差模型,
garch 详细介绍请见链接 https://en.wikipedia.org/wiki/Autoregressive_conditional_heteroskedasticity#GARCH
garch是只需要指定MaxOrder, 不需要指定p/d/q, 对每个分组分别计算出最优的参数,给出预测结果。
使用方式
参考文档 https://www.yuque.com/pinshu/alink_guide/xbp5ky
参数说明
| 名称 | 中文名称 | 描述 | 类型 | 是否必须? | 取值范围 | 默认值 | | —- | —- | —- | —- | —- | —- | —- |
| predictionCol | 预测结果列名 | 预测结果列名 | String | ✓ | | |
| valueCol | value列,类型为MTable | value列,类型为MTable | String | ✓ | 所选列类型为 [M_TABLE] | |
| icType | 评价指标 | 评价指标 | String | | “AIC”, “BIC”, “HQIC” | “AIC” |
| ifGARCH11 | 是否用garch11 | 是否用garch11 | Boolean | | | true |
| maxOrder | 模型(p, q)上限 | 模型(p, q)上限 | Integer | | | 10 |
| minusMean | 是否减去均值 | 是否减去均值 | Boolean | | | true |
| predictNum | 预测条数 | 预测条数 | Integer | | | 1 |
| predictionDetailCol | 预测详细信息列名 | 预测详细信息列名 | String | | | |
| reservedCols | 算法保留列名 | 算法保留列 | String[] | | | null |
| numThreads | 组件多线程线程个数 | 组件多线程线程个数 | Integer | | | 1 |
代码示例
Python 代码
from pyalink.alink import *
import pandas as pd
useLocalEnv(1)
import time, datetime
import numpy as np
import pandas as pd
data = pd.DataFrame([
[1, datetime.datetime.fromtimestamp(1), 10.0],
[1, datetime.datetime.fromtimestamp(2), 11.0],
[1, datetime.datetime.fromtimestamp(3), 12.0],
[1, datetime.datetime.fromtimestamp(4), 13.0],
[1, datetime.datetime.fromtimestamp(5), 14.0],
[1, datetime.datetime.fromtimestamp(6), 15.0],
[1, datetime.datetime.fromtimestamp(7), 16.0],
[1, datetime.datetime.fromtimestamp(8), 17.0],
[1, datetime.datetime.fromtimestamp(9), 18.0],
[1, datetime.datetime.fromtimestamp(10), 19.0]
])
source = dataframeToOperator(data, schemaStr='id int, ts timestamp, val double', op_type='batch')
source.link(
GroupByBatchOp()
.setGroupByPredicate("id")
.setSelectClause("id, mtable_agg(ts, val) as data")
).link(
AutoGarchBatchOp()
.setValueCol("data")
.setIcType("AIC")
.setPredictNum(10)
.setMaxOrder(4)
.setIfGARCH11(False)
.setMinusMean(False)
.setPredictionCol("pred")
).print()
Java 代码
package com.alibaba.alink.operator.batch.timeseries;
import org.apache.flink.types.Row;
import com.alibaba.alink.operator.batch.source.MemSourceBatchOp;
import com.alibaba.alink.operator.batch.sql.GroupByBatchOp;
import com.alibaba.alink.testutil.AlinkTestBase;
import org.junit.Test;
import java.sql.Timestamp;
import java.util.Arrays;
import java.util.List;
public class AutoGarchBatchOpTest extends AlinkTestBase {
@Test
public void test() throws Exception {
List <Row> mTableData = Arrays.asList(
Row.of(1, new Timestamp(1), 10.0),
Row.of(1, new Timestamp(2), 11.0),
Row.of(1, new Timestamp(3), 12.0),
Row.of(1, new Timestamp(4), 13.0),
Row.of(1, new Timestamp(5), 14.0),
Row.of(1, new Timestamp(6), 15.0),
Row.of(1, new Timestamp(7), 16.0),
Row.of(1, new Timestamp(8), 17.0),
Row.of(1, new Timestamp(9), 18.0),
Row.of(1, new Timestamp(10), 19.0)
);
MemSourceBatchOp source = new MemSourceBatchOp(mTableData, new String[] {"id", "ts", "val"});
source.link(
new GroupByBatchOp()
.setGroupByPredicate("id")
.setSelectClause("mtable_agg(ts, val) as data")
).link(
new AutoGarchBatchOp()
.setValueCol("data")
.setIcType("AIC")
.setPredictNum(10)
.setMaxOrder(4)
.setIfGARCH11(false)
.setMinusMean(false)
.setPredictionCol("pred")
).print();
}
}
运行结果
| id | data | pred | | —- | —- | —- |
| 1 | {“data”:{“ts”:[“1970-01-01 08:00:00.001”,”1970-01-01 08:00:00.002”,”1970-01-01 08:00:00.003”,”1970-01-01 08:00:00.004”,”1970-01-01 08:00:00.005”,”1970-01-01 08:00:00.006”,”1970-01-01 08:00:00.007”,”1970-01-01 08:00:00.008”,”1970-01-01 08:00:00.009”,”1970-01-01 08:00:00.01”],”val”:[10.0,11.0,12.0,13.0,14.0,15.0,16.0,17.0,18.0,19.0]},”schema”:”ts TIMESTAMP,val DOUBLE”} | null |