Name: measuring error in scientific data
Uploaded: 2023-09-22T11:49:39.000Z
Duration: 1 min 20 s
Channel: JoVE

Errors in the measurement process are a common problem. Such errors may fall into two categories: Random and Systematic.
Random errors are the result of inconsistency in the measuring process or variations in the quantity being measured. These result in fluctuations, too high or too low, around the true value.
Consider a scientist measuring the length of an earthworm using a caliper. Inconsistency of the scientist to read the scales correctly, or continuous body movement of the earthworm during the measurement, may result in incorrect length measurements.
Random error cannot be avoided, however, it can be averaged out with repeated trials.
Systematic errors are the results of a persistent issue and lead to a consistent discrepancy in measurement. These errors tend to be either all too high or all too low compared to the true value. For instance, weights being measured using an improperly calibrated weighing balance.
These are predictable and mostly instrument-related. However, unlike random error, it cannot be averaged out with repeated measurement.

random and systematic errors

Wetenschappers doen altijd hun best om metingen met de grootst mogelijke nauwkeurigheid en precisie vast te leggen. Soms komen er echter fouten voor. Deze fouten kunnen willekeurig of systematisch zijn. Willekeurige fouten worden waargenomen als gevolg van de inconsistentie of fluctuatie in het meetproces, of variaties in de hoeveelheid zelf die wordt gemeten. Dergelijke fouten variëren van groter of kleiner dan de werkelijke waarde bij herhaalde metingen. Stel je een wetenschapper voor die de lengte van een regenworm meet met behulp van een liniaal. Willekeurige fouten in dit meetproces kunnen het gevolg zijn van de inconsistente methode waarbij de wetenschapper de weegschaal afleest, of als de regenworm beweegt. Willekeurige fouten kunnen niet worden vermeden; het kan echter met herhaalde pogingen worden uitgemiddeld. Systematische fouten komen voort uit een hardnekkig probleem en resulteren in een consistente discrepantie in de metingen. Deze fouten zijn meestal groter of kleiner dan de werkelijke waarde. Deze zijn voorspelbaar en meestal instrumenteel van aard. Een onjuist gekalibreerde weegbalans kan bijvoorbeeld voortdurend voorwerpen wegen die zwaarder zijn dan hun werkelijke waarde. In tegenstelling tot willekeurige fouten kunnen systemische fouten niet worden uitgemiddeld door herhaalde metingen. Deze tekst is overgenomen uit <a href="https://openstax.org/books/chemistry-2e/pages/1-5-measurement-uncertainty-accuracy-and-precision">Openstax, Chemistry 2e, Sectie 1.5: Meetonzekerheid, nauwkeurigheid en precisie.</a>

Random and Systematic Errors

Scientists always try their best to record measurements with the utmost accuracy and precision. However, sometimes errors do occur. These errors can be ...

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Willekeurige en systematische fouten

measuring error in scientific data

Random and systematic errors affect scientific measurements. Random errors cause values to spread around the true value. They make repeated measurements less consistent. Systematic errors shift measurements in the same direction each time.

Understanding both kinds of error helps students judge data quality. Random error can come from small changes during measurement. Systematic error can come from a biased tool or method. Scientists look for these patterns so they can improve results and interpret data more carefully.

Measuring Error in Scientific Data

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Random and systematic errors affect scientific measurements. Random errors cause values to spread around the true value. They make repeated measurements less consistent. Systematic errors shift measurements in the same direction each time. Understanding both kinds of error helps students judge data quality. Random error can come from small changes during measurement. Systematic error can come from a biased tool or method. Scientists look for these patterns so they can improve results and...

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key terms and concepts

Learn how random and systematic errors affect scientific measurements, why they matter, and how they change the way students judge data quality.

Measuring Error in Scientific Data | JoVE K12

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Measuring Error in Scientific Data

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