Which of the following statements about a linear regression model are correct?i) It is possible that a high R-square can result from outliersii) It is always true that the high the R-square, the better the linear regression model iii) Scatterplot can be helpful in identifying the existence of outliers in fitting a regression modeliv) Regression model cannot produce a range of predictions. v) A p-value higher than 0.5 suggests the estimated coefficient is statistically significant. Question 2Answera.i) and v)b.None of the abovec.i) and iii)d.iv) and v)e.i), ii) and iii)
Question
Which of the following statements about a linear regression model are correct?i) It is possible that a high R-square can result from outliersii) It is always true that the high the R-square, the better the linear regression model iii) Scatterplot can be helpful in identifying the existence of outliers in fitting a regression modeliv) Regression model cannot produce a range of predictions. v) A p-value higher than 0.5 suggests the estimated coefficient is statistically significant. Question 2Answera.i) and v)b.None of the abovec.i) and iii)d.iv) and v)e.i), ii) and iii)
Solution
The correct answer is c. i) and iii).
i) It is possible that a high R-square can result from outliers. This is because the R-square measures the proportion of the variance in the dependent variable that is predictable from the independent variable(s). Outliers can significantly impact the regression line and thus the R-square value.
iii) Scatterplot can be helpful in identifying the existence of outliers in fitting a regression model. Scatterplots are a great way to visualize the relationship between two variables. If there are outliers, they will often appear as points that are far away from the general trend of the data.
The other statements are incorrect:
ii) It is not always true that the higher the R-square, the better the linear regression model. A high R-square can be the result of overfitting the model to the data.
iv) A regression model can produce a range of predictions. The predictions are based on the regression line, and for any given value of the independent variable, there is a range of possible dependent variable values that are predicted by the model.
v) A p-value higher than 0.5 does not suggest the estimated coefficient is statistically significant. In fact, it suggests the opposite. A p-value less than 0.05 is typically used to indicate statistical significance.
Similar Questions
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