Inferensia Sampel Kecil untuk Populasi Normal

(Small-sample Inferences for Normal Populations)

Dr. Kusman Sadik, M.Si

Departemen Statistika IPB, 2018/2019

Many investigations, especially those involving costly

experiments, require statistical inferences to be drawn

from small samples ( n ≤ 30, as a rule of thumb).

Since the sample mean 𝑋 will still be used for inferences

about μ, we must address the question, “What is the

sampling distribution of when n is not large?”

With the central limit theorem no longer applicable, more

information concerning the populaon is required for the

development of statistical procedures.

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Sampel Besar (n > 30) Sebaran Normal (Z)

Sampel Kecil (n < 30) Sebaran t-Student

Jumlah

Sampel (n)

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derajat bebas4

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t(0.10, db=5) = 1.476

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𝑇hit = 𝑋 − 𝜇0

𝑆/ 𝑛

Tolak H0 jikap-value < α

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Selesaikan contoh soal ini menggunakan Minitab, kemudian

bandingkan hasilnya dengan jawaban sebelumnya.

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Johnson (Exercise 9.12), hlm. 361

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Johnson (Exercise 9.23), hlm. 362

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Johnson (Exercise 9.23), hlm. 362

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Selesaikan soal ini menggunakan Minitab, kemudian

bandingkan hasilnya dengan jawaban Anda pada No.2 di

atas.

Johnson (Exercise 9.29), hlm. 363

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Johnson (Exercise 9.63), hlm. 377

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Johnson (Exercise 9.63), hlm. 377

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Selesaikan soal ini menggunakan Minitab, kemudian

bandingkan hasilnya dengan jawaban Anda pada No.5 di

atas.

Johnson, R.A. and Bhattacharyya, G.K. 2010.

Statistics, Principles and Methods 6th. John Wiley

& Sons, Inc., New York.

Montgomery, D.C. 2013. Design and Analysis of

Experiments 8th. John Wiley & Sons, Inc.,

Canada.

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kusmansadik.wordpress.com

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