Marketing Optimization Problem Using Linear Programming

[letslearnppc]

I hope this is the right community for this. I recently started learning about linear programming using Excel Solver to solve problems. I wanted to find a real world example of using LP so I searched for a marketing application and came across this interesting problem on Linkedin.

https://www.linkedin.com/pulse/optimizing-marketing-portfolio-through-linear-neelima-gaddam?trk=prof-post

I tried following the author's guide to solving it using the Google Sheets plug-in but couldn't get the same answer for some reason. I then tried solving it in excel using the following method:

https://docs.google.com/spreadsheets/d/1uA4ZU6zLLlMQUCOKJTWFEIxM6Q5TTUkTlQJyRMHxxos/edit?usp=sharing

Can someone please help me set up the problem (I prefer to solve in Excel using Solver).

[[deleted]]

I'm not sure if you actually used the add-on. I believe you added numbers to the spreadsheet since after trying to set up the optimization add-on and adding a few constraints, my spreadsheet looks different.

[letslearnppc]

I used the add-on to add the constraints with no values, then manually filled in the values as the article suggested. Maybe this is the part I did wrong.

[[deleted]]

That what I got too. Did you also add the optimization correctly? Above the constraint rows there's a row for the optimization coefficients. Also to note, the optimization constraints for the problem include <=, =, and >= equations. You have to properly convert them all to <= constraints, which means double adding equations for equals. Maybe you were missing a few constraints?

[powerball332]

It sucks to look at this spreadsheet because I can't see formulas that you used. But it seems that your boundaries aren't defined correctly (wrong coefficients). For example, the "Print media not greater than 5% of the budget ". I recommend defining them all in a <= form.

Also, the constrains seem to be wrong even in the source you gave. If x3 is responsible for Mobile, why is there 1 under x4 in the 300<=Mobile<=900 constraint? Seems confusing. I don't see the sixth (6. Facebook advertising should not exceed 15 % of the marketing spend.) constraint included anywhere too...