範例：中值-中值遞歸

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範例：中值-中值遞歸

使用 medfit 函數計算數據集的「中值-中值」直線擬合。

1. 定義數據集。

最後一個點是離群值：

2. 呼叫 medfit 函數求解「中值-中值」直線擬合的係數。使用這些係數定義「中值-中值」線。

3. 呼叫 line 函數求解最小平方線性擬合的係數。使用這些係數定義最佳擬合線。

4. 繪製數據點與前文定義的兩條線。

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      <traces>
        <trace>
          <traceStyle color="#FF00008B" symbol="x" line-weight="1" line-style="None">線條</traceStyle>
        </trace>
        <trace num-of-points="500">
          <traceStyle color="#FF000000" symbol="none" line-weight="1" line-style="Solid">lines</traceStyle>
        </trace>
        <trace num-of-points="500">
          <traceStyle color="#FFFF0000" symbol="none" line-weight="1" line-style="Solid">線條</traceStyle>
        </trace>
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            <startValue>
              <real xmlns="http://schemas.mathsoft.com/math50">-10</real>
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              <real xmlns="http://schemas.mathsoft.com/math50">10</real>
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        <yAxis legend-position="PlotBoundaryLeft" rank="1">
          <axisLine position="origin" positionticmark="5" />
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            <tickMarks display="true" />
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              <math>
                <id xmlns="http://schemas.mathsoft.com/math50">Y</id>
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              <math>
                <placeholder xmlns="http://schemas.mathsoft.com/math50" />
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            </plotEquation>
            <plotEquation>
              <math>
                <apply xmlns="http://schemas.mathsoft.com/math50">
                  <id>med</id>
                  <id>x</id>
                </apply>
              </math>
              <math>
                <placeholder xmlns="http://schemas.mathsoft.com/math50" />
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            </plotEquation>
            <plotEquation>
              <math>
                <apply xmlns="http://schemas.mathsoft.com/math50">
                  <id>lsq</id>
                  <id>x</id>
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              <real xmlns="http://schemas.mathsoft.com/math50">-120</real>
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              <real xmlns="http://schemas.mathsoft.com/math50">80</real>
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線性擬合受離群值的影響比受「中值-中值」擬合的影響來得大。

相關主題

中值-中值遞歸

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