| season | numeric | 4 digit number indicating to which season(s) the
specified timeframe belongs to. | 
| season_type | character | REG or POST indicating if the game belongs to regular
or post season. | 
| game_week | numeric | Season week | 
| team_abb | character | Abbreviation of Team of Player | 
| player_id | numeric | ESPN Player ID | 
| name_short | character | Short name of player (First Initial, Last Name) | 
| rank | numeric | QBR Rank in specified timeframe | 
| qbr_total | numeric | Adjusted Total QBR, which adjusts quarterback play on
0-100 scale adjusted for strength of opposing defenses played. | 
| pts_added | numeric | Number of points contributed by a quarterback above the
average level QB | 
| qb_plays | numeric | Total dropbacks for the quarterback (excludes
handoffs) | 
| epa_total | numeric | Total Expected Points Added by quarterback, calculated
by ESPN Win Probability Model | 
| pass | numeric | Expected Points Added on pass plays | 
| run | numeric | Expected Points Added on run plays | 
| exp_sack | numeric | Expected EPA Added on Sacks | 
| penalty | numeric | Expected Points Added on penalties | 
| qbr_raw | numeric | Raw total QBR, does not adjust for strength of opposing
defenses played. | 
| sack | numeric | Expected Points Added on sacks | 
| name_first | character | First Name of Quarterback | 
| name_last | character | Last Name of Quarterback | 
| name_display | character | Full Name of Quarterback | 
| headshot_href | character | Link to ESPN Headshot of Player | 
| team | character | Full Team Name of Player | 
| qualified | character | True/False indicator of whether or not player meets
minimum play requirement |