A question that a economist would asked about ancient gold crown artifact
Answers
Where is the pic!?! i can't answer it without picture
42.1% of variation in the response is explained by the regression line
Step-by-step explanation:
Correlation coefficient is a measure which tells us that how strongly are two variables under study are linearly related to each other i.e correlation coefficient gives the strength of linear association between the variables.
If the magnitude of correlation coefficient is closer to 1, it indicates a strong linear relationship. If the magnitude of correlation coefficient is closer to 0, it indicates a weak linear relationship.
There is another variable known as "Coefficient of Determination", which is equal to square of Correlation Coefficient. Coefficient of Determination tells us that what percentage of variation in the response of the study can be explained by the regression line.
This means, for this question we need to calculate the Coefficient of Determination.
Correlation coefficient = r = 0.649
Coefficient of Determination = R = r² = (0.649)²= 0.421 = 42.1 %
This means that 42.1% of variation in the response is explained by the regression line.
An economist conducted a study of the possible association between weekly income and weekly grocery expenditures. Of particular interest was whether higher income would result in shoppers spending more on groceries. A random sample of shoppers at a local supermarket was obtained. A questionnaire was administered asking about the weekly income of each shopper's family and their grocery bill for that week. The explanatory variable is:
A. weekly income.
B. weekly expenditure.
C. gender.
D. None of the answer options is correct
A. weekly income.
Step-by-step explanation:
Explanatory variables are variables that shows the difference in response variables, the explanatory variable influences the response variable. It is an independent variable that can be manipulated. The independent variable helps explain the response variable.
In this case, the explanatory variable is the weeky income because the respose variable (weekly expenditure) variation depends on it. The economist wants to use the weekly income of each shoppers family to determine how much they will spend on groceries. So, the weekly income is the explanatory variable.
The answer cannot be determined from the information provided.
Option B.
Explanation:
A linear regression line has an equation in the form Y = a + bX, where X stands for the explanatory variable and Y is used to denote the dependent variable in the equation. The slope of the line is b, and a is the intercept (the value of y when x = 0).
A regression line (LSRL - Least Squares Regression Line) is a straight line that explains how a dependent variable y changes as an explanatory variable x changes. The line is a mathematical model used to predict the value of y for a given x. Regression requires that we have an explanatory and response variable.