Statistics I207910 marksNumerical: correlation and regressionKarl Pearson's coefficient of correlation
Question What are the assumptions of Pearson's correlation? Bradford Electric Illuminating is studying the relationship between kilowatt-hours (thousands) used and the number of rooms in private single-family residences. A random sample of 5 houses yields the following. i. Find the correlation coeff
Question
What are the assumptions of Pearson's correlation? Bradford Electric Illuminating is studying the relationship between kilowatt-hours (thousands) used and the number of rooms in private single-family residences. A random sample of 5 houses yields the following.
$$\begin{array}{c|ccccc} \text{Number of rooms} & 11 & 10 & 14 & 7 & 9 \ \hline \text{Kilowatts-hours (thousands) used} & 9 & 8 & 11 & 5 & 9 \ \end{array}$$
i. Find the correlation coefficient between the number of rooms and kilowatts-hours used. Interpret the result.
ii. Determine the regression equation of kilowatts hours used on the number of rooms. Interpret the value of the regression coefficient.
iii. Estimate the kilowatts-hours used for an 8 rooms house.
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- Linear relationship: The two variables X and Y have a linear relationship. 2. Normality: The variables follow a bivariate normal distribution. 3. Continuous, quantitative data: Both variables are measured on an interval or ratio scale. 4. Homoscedasticity: Variance of Y is constant across valu...