Backtesting the Daily Fantasy Optimizer

The Daily Fantasy Optimizer is a flexible tool for implementing custom DFS strategies. But sometimes it is hard to understand how well one strategy performs relative to another due to noise in DFS scoring. Our backtesting mode is here to help!

This feature allows you to:

• Test our your favorite optimizer strategies on past slates
• See automatic calculation of the actual fantasy points scored for each lineup generated
• Compare multiple builds for a given slate
• Upload data from a past contest to see where your lineups would have landed with respect to top scorers
• Visualize your results

This tutorial walks you through the basics of using the backtesting mode with either DraftKings or FanDuel.

Step 1: Enable backtesting

To enable backtesting, you'll have to first create an account. You can do this by clicking the sign in button in the top right of the page and following the instructions. Once you have an account, you'll see a new button on the main optimizer page that can be clicked to activate backtesting mode, as shown below.

Step 2: Generate your first build

The DFO backtesting tool works by grouping generated lineups into what we call "builds." A build is a set of lineups that were generated with a specific strategy. For example, if you'd like to study the effect of maximum overlap = 3 versus 8, you could create two builds, one with a max overlap of 3 and one with a max overlap of 8. Each build must be populated with lineups, and the number of lineups associated with each build can be different. You can also mix settings for a given build (generate 10 lineups with no stacks and then 10 more with a stack, all in the same build). When visualizing results, the data will be categorized by build.

Generating the first build is as simple as using the optimizer as you normally would. Select your desired settings and click the "Generate Lineups" button. Once you have populated the first build with at least one lineup, the "View Results" button will become active. This button opens up a summary of your current builds with information such as the number of lineups in the build, and the build's average, minimum and maximum points for the given historical slate. You can edit the default build name at this stage, if desired.

Step 3: Create a second build for comparison

One of the main benefits of the backtesting tool is the ability to create multiple builds for comparison. To create a second build, simply click the "Add Second Build" button, give the build a name, and then click "Create."

Once the second build has been created, you'll be returned to the optimizer screen so that you can select desired settings and generate lineups for your new build. You can switch between builds using the selector which is located on the bottom bar of the optimizer as well as at the top of the results window. You can also easily create additional builds by hitting the "plus" icon next to the build selector.

Step 4: View backtesting results

Once you have created and populated a number of backtesting builds, you can compare them by clicking the "View Results" button. This will open a window that allows you to view overall stats for each build, visualize lineup performance, and browse the details of the individual builds (similar to the typical Daily Fantasy Optimizer "View Lineups" menu). You can also clear lineups on a build-by-build basis from this window.

Other features: Upload contest data

The Daily Fantasy Optimizer backtesting tool also allows you to upload contest data to see how your lineups would have performed relative to other players. The contest data is automatically displayed in the "Contests" tab as well as the "Visualization" tab once uploaded. You can turn it off by clicking on the contest in the plot legend or you can remove the contest by deleting it in the "Contests" tab.

Other features: Compare projections to points scored

Finally, you can view the projected points versus actual points for each slate from the main optimizer page by clicking on the "Compare Projections" button. Here you can see what players under- or overperformed relative to their projection. You can also use this feature to check out how well your custom projections do by uploading them prior to opening the plot.

Happy optimizing! If you have any questions or feedback, please don't hesitate to contact us through our contact form or join our Discord server to get involved with the community, ask questions, report bugs, or request new features!