Team Stack App

Team stacking is pivotal for daily fantasy baseball success. It's not only important to pick the right team to stack, but to also pick the right players on that team to stack. We set out to design an application to serve as your command center to optimize your hitter stacks for MLB contests. The result: the ASA Team Stack app.

App interface
  1. Site input - Select the site scoring format you want to view.
  2. Team input - Select the team you want to view in the app output tabs below. You can only view one team at a time in the "Runs vs. Team FP" tab (7), and you can only view players from the team you select in the other three player tabs (8-10). For players that have played for multiple teams in the selected date range, you will only view data of the such players produced while on the specified team.
  3. Player(s) input - Select the players whose data you want to view in the player-level tabs (8-10). The default is set to show the players from the specified team with the eight highest medians.
  4. Player vs. runs comparison type - This input relates to the "Runs vs. Player FP" tab (9). Through this input, you can specify if you want the output to plot team runs (x) vs. players' fantasy points scored or the proportion of the team's total fantasy points each player accounts for (y).
  5. Date range input - Specify the date range for the data which you want to consider.
  6. Raw data download button - Download the batting box score data for the team, players, and date selected.
  7. Runs vs. Team FP tab - This tab displays a box-and-whisker plot of the team's total fantasy points scored across the different run totals they have scored during the specified date range. This article offers a short description of how to interpret box-and-whisker plots. Beneath the boxes is a trendline showing the general relationship between runs and total batting fantasy points specific to the team specified in input (2). This plot can be used in conjunction with pre-game implied run totals to develop crude projection for a full team stack (even though you can only select at most 4-5 players from a single offense.
  8. Player FP Proportions tab - This tab displays box-and-whisker plots for the historical proportion of a team's single-game fantasy point totals accounted for by each of the players specified in input (3). While this tab doesn't account for specific hitter-pitcher matchups, one could crudely use this tab in conjunction with (7) to project a median expectation for fantasy points scored by a player conditional on expected runs scored by the team by multiplying a player's median proportion by the median team total fantasy points associated with the team's implied point total.
  9. Runs vs. Player FP tab - While the player proportions tab (8) provides a general summary of proportion of team total fantasy points accounted for by each player, it doesn't provide any context about the conditions in which players contribute higher and lower proportional fantasy point totals to their team's total. This tab plots the player-specific trendlines between team runs scored and player fantasy point totals (default) or proportion of team fantasy points, depending on selection in input (4).
  10. Player FP Correlation tab - This tab allows you to consider the historical correlation between all the players selected in input (3). This matrix only considers data points in which both players at the intersecting cell were starters. For guidance on interpreting correlation coefficients, consult this short Wikipedia page. This is a computationally intensive page to generate, so you may experience some lag in the output of this page after changing or initializing any of the inputs.