Name: grubbs test for spotting data outliers
Uploaded: 2024-04-04T10:51:12.000Z
Duration: 1 min 2 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Chemistry

CHEM.2

CHEM.2.C

quantifying-and-rejecting-outliers-the-grubbs-test

Quantifying and Rejecting Outliers: The Grubbs Test

グラブスの検定は、ディクソンのQ検定と同様に、正規分布を持つデータの外れ値を特定するための統計的検定です。ここでは、観測値の数は 7 以上である必要があります。
特定のデータセットについて、この検定では、サンプルの標準偏差に対する疑わしい値と平均値との絶対差の比であるグラブスの統計量Gを計算します。
次に、計算されたG値は、特定の信頼水準および観測値の数に対するGの表形式の臨界値と比較されます。
計算された G 値が G の臨界値を超えると、疑わしい観測値はデータの外れ値と見なされ、拒否されます。 
あるいは、計算された G 値が G の臨界値よりも小さい場合、データは疑わしい観測値を保持します。

外れ値の定量化と拒否: グラブス テスト

場合によっては、データ セットには、他のデータから大きく逸脱した数値観測値が記録されることがあります。データが正規分布していると仮定すると、グラブス検定と呼ばれる統計手法を使用して、観測値が本当に外れ値であるかどうかを判断できます。両側グラブス検定を実行するには、まず外れ値と平均の差の絶対値を計算します。次に、この差とサンプルの標準偏差の間の比率を計算します。この数値はグラブス統計量「G」として知られています。計算された G 値が、特定の信頼水準および観測値の G 臨界値を超える場合、疑わしい観測値は外れ値とみなされ、データセットから削除されます。逆に、計算された G 値が臨界 G 値より小さい場合、疑わしい観測値は外れ値とはみなされないため、データセットに保持されます。

グラブスの検定は、ディクソンのQ検定と同様に、正規分布を持つデータの外れ値を特定するための統計的検定です。ここで、数...

Education

JoVE Core

Analytical Chemistry

分析化学

Unit 1

ユニット1

Chemical Applications of Statistical Analyses

統計分析の化学的応用

chemical-applications-of-statistical-analyses

KEY TERMS AND CONCEPTS

主要用語と概念

grubbs test for spotting data outliers

The Grubbs test is a statistical way to spot a possible outlier in a data set. It is used when the data is assumed to follow a normal distribution. A Grubbs test helps decide whether one unusual numerical value should be treated as a true outlier.

To run a two-tailed Grubbs test, first find the absolute difference between the questionable value and the mean. Then divide that difference by the sample standard deviation. The result is the Grubbs statistic, or G.

Next, compare the calculated G value with the G critical value for the chosen confidence level and the number of observations. If the calculated G is larger, the questionable value is considered an outlier and removed from the data set. If the calculated G is smaller, the value is not considered an outlier and is kept in the data set.

Grubbs Test for Spotting Data Outliers

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The Grubbs test is a statistical way to spot a possible outlier in a data set. It is used when the data is assumed to follow a normal distribution. A Grubbs test helps decide whether one unusual numerical value should be treated as a true outlier. To run a two-tailed Grubbs test, first find the absolute difference between the questionable value and the mean. Then divide that difference by the sample standard deviation. The result is the Grubbs statistic, or G. Next, compare the calculated G...

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key terms and concepts

Learn how the Grubbs test checks a normal data set for a possible outlier by comparing the G statistic with the critical value.

Grubbs Test for Spotting Data Outliers | JoVE K12

JoVE Core 分析化学 は、複雑な化学原理をアニメーションで視覚化することで、SI 単位から NMR 分光法を含むトピックをよりわかりやすくします。実験を撮影した実写動画では、これらの概念が世界中の研究所でどのように応用されているかを取り上げています。

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Grubbs Test for Spotting Data Outliers

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