STAT_6 D_PI'ViEW Progress save Score: 6/18 5/9 answered 0 Question 5 v We also might worry about the appropriateness of the model if we notice an extreme observation that affects the value of the line. Recall from earlier activities that an outlier is an extreme observation that is far away from the rest of the data. In fitting a regression line, an outlier can also be an observation that does not t the trend of the data as well. We call this type of outlier an inuential point. This point drastically changes the equation of the line, consequently increasing the values of all of the residuals. An influential point appears to "pull" the line towards its value. We will also study how these points affect R2. It is important to note that not all outliers affect the equation of the line, so we will need to investigate. Open the DCMP Linear Regression tool at msz/dcmathpathwaysshinyappsio/LinearRegression/ Open the "Animal Longevity" dataset. This is the same dataset that was used in Question 1. Make sure that gestation is the explanatory variable and longevity is the response variable. Part A: Find the point on the graph corresponding to the elephant by hovering over the points. Is this observation an outlier that does not fit the trend? Hint Where does the point lie in relation to the line of best t? O No 0 Yes Part B: What is R2 for this dataset? See the table below the scatterplot. R2 = 1% See the table below the scatterplot. R2=l % Part C: Select the box on the left side of screen that says "Click to Remove Points." Remove the point corresponding to the elephant by either clicking on the scatterplot or by highlighting the elephant row in the data table and deleting it. How does R2 change when you remove the elephant from the dataset? O R2 increases 0 R2 decreases O R2 stays the same Part D: Why do you think this is? How does removing the elephant affect the relative amount of variability that is explained by the linear relationship? Edit' Insert' Formats' B I U X2 A v A ' 0 _X3 __ '2": @d\"?ll@v2+2fl=l v A IIIII . IIIII E Calculator Submit Question 0 Question 7 v Now, reload the "Animal Longevity" dataset so that the data for the elephant are included once again. Part A: Find the point on the graph corresponding to the hippopotamus. Is this observation an outlier? Hint Where does the point lie in relation to the line of best t? 0 No 0 Yes Part B: What is R2 for this dataset? You've already answered this in the previous question. See the table below the scatterplot. R2 : % Part C: Select the box on the left side of screen that says \"Click to Remove Points." Remove the point corresponding to the hippopotamus by either clicking on the scatterplot or by highlighting the hippopotamus row in the data table and deleting it. How does R2 change when you remove the hippopotamus from the dataset? O R2 stays the same 0 R2 increases 0 R2 decreases CI\" 0/4 pt: Part C: Select the box on the left side of screen that says "Click to Remove Points." Remove the point corresponding to the hippopotamus by either clicking on the scatterplot or by highlighting the hippopotamus row in the data table and deleting it. How does R change when you remove the hippopotamus from the dataset? OR' stays the same O R' increases O R' decreases Part D: Why do you think this is? How does removing the hippopotamus affect the relative amount of variability that is explained by the linear relationship? Edit Insert Formats BIU X X A YAY Calculator Submit QuestionQuestion 8 Consider this plot again, which we saw in a previous question. The scatterplot has R2 = 98.2%. Scatterplot 8 50 40 N 6 10 Determine whether the following statement is true or false: If the scatterplot of two variables has a high R value, then a line is an appropriate model for the relationship between the variables. Hint What conditions must be satisfied in order for a linear regression model to be appropriate? O True O False