least-squares estimation)으로 추정된다. 여기서 잔차(residual)는 관찰치 와추정치 = + 의차이이다.
단순회귀모형은 프로그램 R에서 lm()을 이용해서 단순회귀분석을 할 수 있다.
lm(종속변수 ~ 독립변수)
독립변수들 간의 상관관계가 높다는 것은 중복된 정보를 모형에 넣어준다는 뜻이므로 변수의 낭비임
Research Purpose
Nowadays, there are many different models of cars and their prices range.
We want to know what the factors are which affect the selling price of the car and how much each variable explains the selling price.
Research Process
To determine if there is a correlation between various factors and the selling price of the car, the multiple linear regression model was used
regression model was used. First, 10 explanatory variables that are likely to affect selling price of the car were potentially set and the data were collected. In this course, we referred to website (http://www.enuri.com/car) that sells new cars. Next, the standard regression assumptions were checked. Finally, fitness of model was examined by deciding whether the price of the car can be explained
Ⅱ. Theory
1. 기본 물성값
이번 프로젝트에서 선택한 물질은 에탄올과 DMC(ethanol/Dimethyl carbonate)이다. 그 물성치들은 아래와 같다.
MW
ρ/gcm3
R J. Gmehling, U. Onken, and W. Arlt, Vapor-Liquid Equilibrium Data Collection, Chemistry Data Wervice, DECHEMA, Frankfurt/Main, 1984-1990
Q1)
46.07
0.7851
2.1055
1.9728
(1) 에탄올 (ethanol, C2H5OH)