範列：核平滑法

函數 > 數據分析 > 平滑 > 範列：核平滑法

範列：核平滑法

使用 ksmooth 函數平滑處理數據集。

1. 定義隨機數據集。

按一下以複製此運算式

按一下以複製此運算式

按一下以複製此運算式

按一下以複製此運算式

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  <math xml:lang="zh_TW">
    <define xml:lang="zh_TW" xmlns="http://schemas.mathsoft.com/math50">
      <apply xml:lang="zh_TW">
        <indexer xml:lang="zh_TW" />
        <id xml:lang="zh_TW" label="None">Y</id>
        <id xml:lang="zh_TW" label="None">i</id>
      </apply>
      <apply xml:lang="zh_TW">
        <plus xml:lang="zh_TW" />
        <apply xml:lang="zh_TW">
          <indexer xml:lang="zh_TW" />
          <id xml:lang="zh_TW">X</id>
          <id xml:lang="zh_TW">i</id>
        </apply>
        <apply xml:lang="zh_TW">
          <id xml:lang="zh_TW">rnd</id>
          <real xml:lang="zh_TW">5</real>
        </apply>
      </apply>
    </define>
    <resultFormat xml:lang="zh_TW">
      <decimal precision="round-trip-decimal-places" show-trailing-zeros="false" radix="dec" imaginary-value="i" xml:lang="zh_TW" />
      <matrix size="12,12" offset="0,0" show-indices="false" xml:lang="zh_TW" />
    </resultFormat>
  </math>
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2. 定義核平滑法的頻寬。

按一下以複製此運算式

選取頻寬時請務必謹慎。頻寬過大會使得細節不見，因為它會平均整個數據集。頻寬過小會在經過平滑處理的數據中建立人工的細節。

3. 呼叫 ksmooth 函數對數據集執行核平滑法。

按一下以複製此運算式

4. 在平滑處理前後繪製數據集。

按一下以複製此運算式

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        <trace resultRef="0" xml:lang="zh_TW">
          <traceStyle color="#FF00008B" symbol="x" line-weight="1" line-style="None" xml:lang="zh_TW">線條</traceStyle>
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        <trace resultRef="1" xml:lang="zh_TW">
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            <gridLabels display="true" xml:lang="zh_TW" />
            <gridLines xml:lang="zh_TW" />
            <tickMarks display="true" xml:lang="zh_TW" />
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          <axisLabel xml:lang="zh_TW" />
          <markers xml:lang="zh_TW" />
          <numberFormat xml:lang="zh_TW">
            <decimal precision="3" show-trailing-zeros="false" radix="dec" imaginary-value="i" xml:lang="zh_TW" />
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          <plotEquations xml:lang="zh_TW">
            <plotEquation xml:lang="zh_TW">
              <math xml:lang="zh_TW">
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            <gridLabels display="true" xml:lang="zh_TW" />
            <gridLines xml:lang="zh_TW" />
            <tickMarks display="true" xml:lang="zh_TW" />
          </axisGrid>
          <axisLabel xml:lang="zh_TW" />
          <markers xml:lang="zh_TW" />
          <numberFormat xml:lang="zh_TW">
            <decimal precision="3" show-trailing-zeros="false" radix="dec" imaginary-value="i" xml:lang="zh_TW" />
          </numberFormat>
          <plotEquations xml:lang="zh_TW">
            <plotEquation xml:lang="zh_TW">
              <math xml:lang="zh_TW">
                <id xml:lang="zh_TW" xmlns="http://schemas.mathsoft.com/math50">Y</id>
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                <placeholder xml:lang="zh_TW" xmlns="http://schemas.mathsoft.com/math50" />
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            </plotEquation>
            <plotEquation xml:lang="zh_TW">
              <math xml:lang="zh_TW">
                <id xml:lang="zh_TW" xmlns="http://schemas.mathsoft.com/math50">K</id>
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              <math xml:lang="zh_TW">
                <placeholder xml:lang="zh_TW" xmlns="http://schemas.mathsoft.com/math50" />
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