Subject: Marketing Analytics II - Regression Analysis (RStudio)

My code so far:

--- title: "Homework on Media Mix Modeling" author: "Nicole-Lourdes Fader" output: pdf_document: default html_notebook: default html_document: default ---

In this homework, with help from the following code, you are going to estimate 9 models using different values of $\lambda$ with the estimation data, and using the test data to select the best model.

Please replace "......" with your own code, no need to change any exisiting code.

## First, Load the Data and Get Ready

Finish the code of loading the data file called "sales_ads_use.csv", using command `read.csv()`, and name the data frame as `cardf`

```{r }

datafile

cardf

``` ## Second, Create the Ad-Stock Variables

The code below provides a function for a matrix of ad-stock variables from a matrix of the original per-period marketing variables as the data reads.

```{r }

# AdStockMatrix() Returns the scale matrix for creating the adstock variable from the marketing per-period expenses # Input: # lambda - the discounted value # MM - the matrix with all the marketing variables

AdStockMatrix

z

} ```

Question 1(a): I don't know how to estimate the regression model with different ad-stock variable matrices from different $\lambda$ values. How do I draw that using the 'lm()' function 9 times?

## Third, Estimate the Nine Regression Models Estimate the regression model with different ad-stock variable matrices, that are calculated from different $\\lambda$ values. Using the 'Im() function 9 times to get 9 different estimation results using a loop, and write the code below {r } # Get ready for using the function AdStockMatrix MM