1. Bab 5
Distribusi Normal
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2. Topik distribusi normal distribusi normal standar
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3. Distribusi Probabilitas Kontinu
variabel random kontinu
Values from interval of numbers
Absence of gaps
distribution probabilitas kontinu
Distribution of continuous random variable
Most important continuous probability distribution
distribusi normal
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4. Distribusi Normal “Bell shaped” Symmetrical
Mean, median and mode are equal
Interquartile range equals 1.33 s
Random variable has infinite range
f(X) X 
Mean Median Mode
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5. Model Matematika
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6. Beberapa Distribusi Normal
distribusi normal dengan parameters
 and , berbeda
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7. Menentukan Nilai Probabilitas
Probability is the area under the curve!
f(X) X c d
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8. Tabel yang digunakan?
An infinite number of normal distributions means an infinite number of tables to look up!
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9. Distribution Normal Standar
Cumulative Standardized Normal Distribution Table (Portion)
.02 Z
.00
.01
.5478
0.0
.5000
.5040
.5080
Shaded Area Exaggerated
0.1
.5398
.5438
.5478
0.2
.5793
.5832
.5871
Probabilities
Z = 0.12
0.3
.6179
.6217
.6255
Only One Table is Needed
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10. Contoh Standardized Normal Distribution Normal Distribution
Shaded Area Exaggerated
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11. Standardized Normal Distribution
Contoh
Standardized Normal Distribution
Normal Distribution
Shaded Area Exaggerated
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12. Contoh:
(continued)
Cumulative Standardized Normal Distribution Table (Portion) Z
.00
.01
.02
.5832
0.0
.5000
.5040
.5080
Shaded Area Exaggerated
0.1
.5398
.5438
.5478
0.2
.5793
.5832
.5871
Z = 0.21
0.3
.6179
.6217
.6255
© 2002 Prentice-Hall, Inc.

13. Contoh:
(continued)
Cumulative Standardized Normal Distribution Table (Portion) Z
.00
.01
.02
.4168
-03
.3821
.3783
.3745
Shaded Area Exaggerated
-02
.4207
.4168
.4129
-0.1
.4602
.4562
.4522
Z = -0.21
0.0
.5000
.4960
.4920
© 2002 Prentice-Hall, Inc.

14. Contoh: Standardized Normal Distribution Normal Distribution
Shaded Area Exaggerated
© 2002 Prentice-Hall, Inc.

15. Contoh:
(continued)
Cumulative Standardized Normal Distribution Table (Portion) Z
.00
.01
.02
.6179
0.0
.5000
.5040
.5080
Shaded Area Exaggerated
0.1
.5398
.5438
.5478
0.2
.5793
.5832
.5871
Z = 0.30
0.3
.6179
.6217
.6255
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16. Mengetahui nilai Z pada Probabilitas tertentu
Cumulative Standardized Normal Distribution Table (Portion)
What is Z Given Probability = ?
.01 Z
.00
0.2
0.0
.5000
.5040
.5080
.6217
0.1
.5398
.5438
.5478
0.2
.5793
.5832
.5871
0.3
.6179
.6217
.6255
Shaded Area Exaggerated
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17. Nilai X untuk mengetahui Probabilitas
Standardized Normal Distribution
Normal Distribution
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18. Normal Probability Plot for Normal Distribution
Assessing Normality
(continued)
Normal Probability Plot for Normal Distribution 90 X 60 30 Z -2 -1 1 2
Look for Straight Line!
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19. Normal Probability Plot
Left-Skewed
Right-Skewed 90 90 X 60 X 60 30 Z 30 Z -2 -1 1 2 -2 -1 1 2
Rectangular
U-Shaped 90 90 X 60 X 60 30 Z 30 Z -2 -1 1 2 -2 -1 1 2
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20. Larger sample size
P(X)
Smaller sample size
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21. Populasi Normal Population Distribution Central Tendency Variation
Sampling Distributions
Sampling with Replacement
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22. Populasi tidak Normal Population Distribution Central Tendency
Variation
Sampling Distributions
Sampling with Replacement
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23. Central Limit Theorem
the sampling distribution becomes almost normal regardless of shape of population
As sample size gets large enough…
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24. Standardized Normal Distribution
Contoh:
Standardized Normal Distribution
Sampling Distribution
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