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ÁÖ¿ä³»¿ë°ú Áú¹®
2.1 Distributions of Functions of a Random Variable
- [Q] È®·üº¯¼ö X °¡ ÁÖ¾îÁ³À» ¶§, »õ·Î¿î È®·üº¯¼ö g(X)ÀÇ
ºÐÆ÷´Â ¾î¶»°Ô Á¤ÀǵǴ°¡? - ½Ä (2.1.2)ÀÇ ÀÌÇØ.
- [Q] ÀÌ ¶§, ÇÔ¼ö g´Â ¿¬¼ÓÇÔ¼öÀ̾î¾ß¸¸ Çϴ°¡?
- [Q] ¶Ç´Â, ÇÔ¼ö g´Â ÀÏ´ëÀÏ ´ëÀÀ (Áï, ¿ªÇÔ¼ö°¡ Á¸ÀçÇÏ´Â)
ÇÔ¼öÀ̾î¾ß¸¸ Çϴ°¡? - Á¤¸® 2.1.3
- [Q] È®·üº¯¼ö X °¡ ÁÖ¾îÁ³À» ¶§, g(X)ÀÇ ºÐÆ÷¸¦ ¾Ë¾Æ³»´Â
¹æ¹ý¿¡´Â ¾î¶² °ÍµéÀÌ ÀÖ³ª? -Á¤¸® 2.1.3, 2.1.5, 2.1.8
- Probability integral transformation - Á¤¸® 2.1.10°ú ±×
Áõ¸í
- Probability integral transformation °ú ³¼ö»ý¼º
2.2 Expected Values
- ±â´ë°ªÀÇ Á¤ÀÇ
- [Q] ±â´ë°ªÀÇ Á¸Àç Á¤ÀǸ¦ E(X) < ¶ó°í ÇÏÁö ¾Ê°í E(|X|) < ¶ó°í ÇÑ ÀÌÀ¯´Â?
- [Q] È®·üº¯¼ö XÀÇ ±â´ë°ªÀº Ç×»ó Á¸ÀçÇϴ°¡? - Example
2.2.4 Cauchy random variable
- Á¤¸® 2.2.5
- ½Ä (2.2.3)ÀÇ ÀǹÌ
- È®·üº¯¼ö X °¡ ÁÖ¾îÁ³À» ¶§, »õ·Î¿î È®·üº¯¼ö g(X)ÀÇ ±â´ë°ªÀ»
±¸ÇÏ´Â µÎ °¡Áö ¹æ¹ý
2.3 Moments and Moment Generating Functions
- moment, central moment
- moment generating function (mgf, Àû·ü»ý¼ºÇÔ¼ö)
- [Q] Á¤¸® 2.3.7ÀÇ Áõ¸í¿¡¼ ÀûºÐ°ú ¹ÌºÐÀÇ ¼ø¼¸¦ ¹Ù²Ü ¼ö
ÀÖ´Ù´Â °¡Á¤ÀÌ ÇÊ¿äÇÏ´Ù. ÀÌ °¡Á¤ÀÌ ¸¸Á·µÊÀ» Áõ¸íÇÒ ¼ö Àִ°¡?
- gamma function, gamma pdf
- ¸ðµç È®·üº¯¼öÀÇ mgf°¡ Á¸ÀçÇÏ´Â °ÍÀº ¾Æ´Ï´Ù.
- Àû·ü»ý¼ºÇÔ¼ö(mgf)´Â ºÐÆ÷¸¦ °áÁ¤ÇÑ´Ù. Áï, ¾î¶² È®·üº¯¼öÀÇ
mgf°¡ Á¸ÀçÇÏ¸é ±× mgf´Â À¯ÀÏÇϸç È®·üº¯¼öÀÇ ºÐÆ÷°¡ °áÁ¤µÈ´Ù. - Á¤¸® 2.3.11
b
- ÇÏÁö¸¸ Àû·ü(the infinite sequence of moments)Àº ºÐÆ÷¸¦
°áÁ¤ÇÏÁö ¸øÇÑ´Ù. Áï, ºÐÆ÷°¡ ¼·Î ´Ù¸¥ µÎ È®·üº¯¼ö°¡ µ¿ÀÏÇÑ Àû·üÀ» °¡Áú ¼ö
ÀÖ´Ù. - Example 2.3.10
- [Q] Àû·üÀÌ ºÐÆ÷¸¦ °áÁ¤Çϱâ À§ÇÑ ÃæºÐÁ¶°ÇÀº? - Á¤¸® 2.3.11
a
- [Q] 'È®·üº¯¼öÀÇ Àû·ü»ý¼ºÇÔ¼ö°¡ Á¸ÀçÇÑ´Ù'´Â ¸íÁ¦¿Í 'È®·üº¯¼öÀÇ
(¸ðµç Â÷¼öÀÇ) Àû·üÀÌ Á¸ÀçÇÑ´Ù'´Â ¸íÁ¦´Â µ¿µî(equivalent)ÇÑ°¡?
[A] ¾Æ´Ï´Ù. Exercise 2.36
- mgfÀÇ ¼ö·ÅÀ¸·Î ºÐÆ÷ÀÇ ¼ö·ÅÀ» ¹àÈú ¼ö ÀÖ´Ù. - Á¤¸® 2.3.12¿Í
Example 2.3.13 (Âü°í: 'ÀÌÇ× ºÐÆ÷ÀÇ Æ÷¾Æ¼Û ±Ù»ç'(Example
2.3.13)¸¦ mgfÀÇ ¼ö·ÅÀ» ÀÌ¿ëÇÏÁö ¾Ê°í Á÷Á¢ Áõ¸íÇÒ ¼ö ÀÖ´Ù.)
2.4 Differentiating under an Integral Sign
- [Q] ÀûºÐ°ú ±ØÇÑÀÇ ¼ø¼ ±³È¯ °¡´É¼º(ÀÌ ¹®Á¦´Â 1½Ä¿¡ ÀÇÇØ
¹ÌºÐ°ú ÀûºÐÀÇ ±³È¯ °¡´É¼º ¹®Á¦·Î »ý°¢ÇÒ ¼ö ÀÖ´Ù)Àº ¿Ö Áß¿äÇÑ°¡?
- [Q] ¹ÌºÐ°ú ÀûºÐÀÇ ¼ø¼¸¦ ¹Ù²Ù¸é ¾È µÇ´Â ¿¹Á¦¸¦ µé¾î º¸ÀÚ:
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