The following data gives the monthly sales (in thousands ofdollars) for different advertising expenditures (also in thousandsof dollars) and sales commission percentages.
Sales                  245     138     352    322     228    275     560    366
Advertising        16.5   18.0    22.3    18.4    19.0    19.5   30.0    18.6
Commission      10.5    2.0     4.0      3.5      4.5     1.8      9.0      8.5
- What amount of sales would this model predict for advertisingexpenditures of 25,000 and sales commission of 8%? [Show your codein “R Code†section. Show the answer in “Answer†section. Leave“Comments†section blank.]
- Find the correlation coefficients for advertising expenditureand commission compared to sales. Explain the results of thesefindings. [Show your code in “R Code†section. Show the answer in“Answer†section. Leave “Comments†section blank.]
- At the 5% level of significance, are advertising expenditure orsales commission percentage significant? Why? [Show your code in “RCode†section. Show the answer in “Answer†section. Include themathematical notations of two sets of null and alternate hypothesesand the phrase “advertising expenditure†or “sales commissionpercentage†or “both†along with a justification in a few sentencesin “Comments†section.]
