The World Development Indicators database compiles data on household final consumption expenditure and on the number of fixed broadband Internet subscribers for virtually every country and region in the world. Shown here are data on household final consumption expenditure (in millions of constant 2,000 US$) and the number of fixed broadband subscribers (in thousands) for India for the most recent eight years of available data. Using these data, develop a regression model to predict total household final consumption expenditure by the number of fixed broadband Internet subscribers and by (number of fixed broadband Internet subscribers)² . Compare this model with a regression model to predict total household final consumption by only the number of fixed broadband Internet subscribers. Construct a scatter plot of the data. Does the shape of the plot suggest some alternative models in light of Tukey’s four-quadrant approach? If so, develop at least one other model and compare the model with the other two previously developed.

Which Delivery Method Is Best? At a community college, the mathematics department has been experimenting with four different delivery mechanisms for content in their Intermediate Algebra courses. One method is the traditional lecture (method I), the second is a hybrid format in which half the class time is online and the other half is face-to-face (method II), the third is online (method III), and the fourth is an emporium model from which students obtain their lectures and do their work in a lab with an instructor available for assistance (method IV). To assess the effectiveness of the four methods, students in each approach are given a final exam with the results shown next. Do the data suggest that any method has a different mean score from the others?

(a) What is the response variable in this study? Is it quantitative or qualitative?

(b) What is the factor in this study? How many levels does it have?

(c) Write the null and alternative hypotheses.

(d) State the requirements that must be satisfied to use the oneway ANOVA procedure.

(e) Assuming the requirements stated in part (d) are satisfied, use the following StatCrunch output to test the hypothesis of equal means at the  level of significance.

(f) Shown are side-by-side boxplots drawn in StatCrunch of each delivery method. Do these support the results obtained in part (e)?

(g) Interpret the -value.

(h) Verify the residuals are normally distributed.