정보의 홍수 속에서 살아가는 우리 모두는 혼란에 빠지지 않고 필요한 정보만을 가려내는 일이 얼마나 어려운지 알고 있다. 이러한 어려운 일을 해결하기 위하여 통계의 중요성이 대두되어 대학이나 현장실무에서 이에 대한 요구가 점증 되고 있다. 통계를 이용한 자료의 분석은 그 응용 분야가 자연과학뿐만 아니라 사회과학 등 모든 분야에 걸쳐서 광범위하게 사용되어 진다고 할 수 있다. 평소 학생들과 같이 통계 관련 수업을 진행하면서 겪는 어려움이 있다. 대부분의 통계관련 서적이 내용과 형식에 있어서는 아주 훌륭하게 만들어져 있지만, 이론적인 성향이 강하고 설명을 위하여 주어진 예제들이 우리들의 일상 생활과 동떨어져 있다. 통계 초보인 우리가 접근하기에는 어려움이 따른다. 이러한 어려움을 해결하기 위하여 통계를 처음 접하는 사람들을 대상으로 통계의 기본적인 사고와 더불어 생활 속에서 통계를 쉽게 활용할 수 있도록 생활 속의 통계 해설서를 만들어 보기로 하였다.

이 책에서는 통계의 이론적인 개념과 기법에 접근하기보다는 누구나 쉽게 이해할 수 있도록 하였다. 기본적인 원리를 설명하여 통계기법의 적절성과 그 결과의 의미를 바르게 해석하는 데 필요한 기초적인 내용만을 알기 쉽게 모았다. 아무리 쉽고 기초적인 내용만을 모았다고 하여도 통계의 기초는 숫자이므로 수학적인 내용이 빠질 수는 없다. 그래서 처음 접하는 사람들이 부담 없이 읽기에는 어렵고 까다로운 것이 사실이다. 이 책에서는 가능하면 수학 세계에서의 용어나 기호 대신에 보통의 우리들이 사용하는 용어로 표현하려고 노력하였다. 통계를 구성하는 용어의 정의와 정리 및 성질을 다루면서 가능하면 증명은 생략하였고 꼭 필요할 경우에는 본문에서의 설명으로 그 증명을 대신하였다.

1. 통계의 기초

1.1 통계학 ······························································································ 3

1.1.1 통계학이란? ······················································································ 3

1.1.2 통계학의 발전사 ·············································································· 4

연습문제 ··························································································· 7

1.2 자료의 분류와 정리 ········································································· 8

1.2.1 자료의 분류 ····················································································· 8

1.2.2 자료의 정리 1 ················································································· 9

1.2.3 자료의 정리 2 ················································································· 15

연습문제 ··························································································· 20

1.3 중심 경향값과 산포도 ····································································· 21

1.3.1 중심 경향값 ····················································································· 21

1.3.2 산포도 ······························································································ 30

연습문제 ··························································································· 47

2. 순열과 조합

2.1 경우의 수 ························································································· 51

연습문제 ··························································································· 60

2.2 순열 ·································································································· 61

연습문제 ··························································································· 77

2.3 조합 ·································································································· 78

연습문제 ··························································································· 83

2.4 분할 ·································································································· 84

3. 확률

3.1 확률 ·································································································· 99

3.1.1 시행과 사건 ····················································································· 99

3.1.2 합사건과 곱사건 그리고 배반사건과 여사건 ································ 100

3.1.3 확률이란? ······················································································· 103

연습문제 ························································································· 114

3.2 확률의 계산 ··················································································· 115

3.2.1 확률의 덧셈정리와 여사건의 확률 ················································ 115

3.2.2 조건부확률과 확률의 곱셈정리 ····················································· 118

3.2.3 사건의 독립과 종속 ······································································· 124

연습문제 ························································································· 130

4. 통계

4.1 확률분포 ························································································· 133

4.1.1 이산확률변수와 확률분포 ······························································ 133

4.1.2 연속확률변수와 확률분포 ······························································ 137

4.1.3 확률변수의 평균과 분산 ································································ 141

4.1.4 이항분포와 그 성질 ······································································· 147

4.1.5 포아송분포와 그 성질 ··································································· 155

4.1.6 연속확률분포와 그 성질 ································································ 160

연습문제 ························································································· 168

4.2 표본분포와 통계적 추정 ································································ 169

4.2.1 모집단과 표본 ················································································ 169

4.2.2 모평균의 추정 ················································································ 187

4.2.3 모비율의 추정 ················································································ 192

연습문제 ························································································· 199