Name: student's t-test for significance checks
Uploaded: 2024-04-04T10:51:12.000Z
Duration: 1 min 9 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Chemistry

CHEM.2

CHEM.2.C

comparing-experimental-results-student-s-t-test

Comparing Experimental Results: Student's t-Test

Yöntemin, numunenin veya analistin değiştirilmesinin analiz sonuçları üzerindeki etkisi, bir çift deneyden yalnızca birinin değiştirilmesiyle incelenir.
T-testi, bir ortalamanın istatistiksel anlamlılığını diğerinin ortalama değeriyle veya bilinen bir değerle karşılaştırır.
Bir t-testinde, eşleştirilmemiş veriler aynı kaynaktan gelen iki bağımsız veri kümesidir. Eşleştirilmiş veriler, örneğin bir dizi örnek üzerinde iki farklı yöntemden iki küme gibi iki ilgili veri kümesidir.
Test istatistiği, bilinen bir değer için seçilen güven aralığından türetilir. Seçilen bir anlamlılık düzeyinde belirli bir serbestlik derecesi için tablo haline getirilmiş test istatistiği değeriyle karşılaştırıldığında, eski değer ikincisinin aralığı içindeyse, sıfır hipotezi kabul edilir.
Tek kuyruklu bir test YALNIZCA bir artış veya YALNIZCA bir azalma ararken, iki kuyruklu bir test her iki yönde de bir değişiklik arar.

deneysel sonuçların karşılaştırılması: Öğrenci t-testi

T testi, örnek ortalamasını bir popülasyon ortalaması ile karşılaştırmak veya iki veri kümesinden iki ortalamayı karşılaştırmak için kullanılan istatistiksel bir yöntemdir. Test istatistiği, seçilen bir güven aralığında veri setindeki standart sapma, ortalama ve ölçüm sayısından hesaplanır ve ardından bu güven düzeyindeki kritik değerlerin yer aldığı bir tablo ile karşılaştırılır. Test istatistiği kritik değerden küçükse sıfır hipotezi kabul edilir. Bu durumda ortalamalar arasındaki farkın istatistiksel olarak anlamlı olmadığını ve bu nedenle belirsiz (rastgele) hatalardan kaynaklandığını belirtiyoruz. Test istatistiği kritik değerden büyükse sıfır hipotezi reddedilir. Bu durumda ortalamalar arasındaki farkın istatistiksel olarak anlamlı olduğunu ve rastgele hatalarla açıklanamayacağını belirtiyoruz. Farklılık yöntemdeki, örneklemedeki, analistlerin kendilerindeki hatalardan veya gerçek fenomenolojik farklılıklardan kaynaklanmaktadır. İstatistikte t-testleri eşleştirilmiş verilerin yanı sıra eşlenmemiş veriler üzerinde de yapılabilir. Eşleştirilmemiş veriler, aynı kaynaktan alınan iki grup tekrarlanan ölçümdür; eşleştirilmiş veriler, karşılaştırma için aynı numuneler veya denekler üzerinde iki farklı yöntemden veya iki farklı zaman noktasında alınan verileri ifade eder. T testinde normal dağılım eğrisinin yalnızca bir tarafı kullanıldığında, bu tek kuyruklu bir testtir. T testinde dağılımın her iki tarafı da kullanılıyorsa test iki kuyrukludur.

Deneysel Sonuçların Karşılaştırılması: Öğrenci T-testi

Yöntemin, numunenin veya analistin değiştirilmesinin analiz sonuçları üzerindeki etkisi, bir çift deneyden yalnızca birinin değiştirilmesiyle incelenir.
Bu ...

Education

JoVE Core

Analytical Chemistry

Analitik Kimya

Unit 1

Ünite 1

Chemical Applications of Statistical Analyses

İstatistiksel Analizlerin Kimyasal Uygulamaları

chemical-applications-of-statistical-analyses

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

student's t-test for significance checks

Student's t-test is a statistical tool for checking whether two means are different in a meaningful way. It can compare a sample mean with a population mean, or it can compare the means from two data sets. The test uses the mean, standard deviation, and number of measurements, along with a chosen confidence interval.

The test statistic is then compared with a table of critical values at that confidence level. If the test statistic is smaller than the critical value, the null hypothesis is accepted. That means the difference between the means is not statistically significant and is likely due to random, indeterminate errors.

If the test statistic is higher than the critical value, the null hypothesis is rejected. In that case, the difference is statistically significant and cannot be explained by random errors alone. The cause may come from the method, the sampling, the analyst, or a real difference in the phenomenon being studied.

Student's t-tests can be used with unpaired or paired data. Unpaired data are two sets of replicate measurements from the same source. Paired data are measurements taken on the same samples or subjects with two methods, or at two different time points, for comparison. The test can also be one-tailed, when only one side of the normal distribution curve is used, or two-tailed, when both sides are used.

Student's t-Test for Significance Checks

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comparing experimental results: student's t-test

Student's t-test is a statistical tool for checking whether two means are different in a meaningful way. It can compare a sample mean with a population mean, or it can compare the means from two data sets. The test uses the mean, standard deviation, and number of measurements, along with a chosen confidence interval. The test statistic is then compared with a table of critical values at that confidence level. If the test statistic is smaller than the critical value, the null hypothesis is...

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key terms and concepts

Learn how Student's t-test compares means, uses critical values, and helps decide whether a result is statistically significant in high school science.

Student's t-Test for Significance Checks | JoVE K12

JoVE Core Analitik Kimya, karmaşık kimyasal prensiplerini anlaşılır, ilgi çekici animasyonlara dönüştürerek basitleştirir ve SI Birimlerinden NMR spektroskopisine kadar konuları daha erişilebilir ve anlaşılır hale getirir. Buna ek olarak, bilim insanlarının yer aldığı videolar, bu kavramların dünya çapındaki laboratuvarlarda yürütülen gerçek dünya araştırmalarındaki uygulamalarını gösterir.

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Student's t-Test for Significance Checks

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