Nationals 'Fielding Weekly' #7

This covers more than a week, owing to a delay caused by the SABR annual convention in Washington, D.C. The data is drawn from Fangraphs' Ultimate Zone Rating (UZR) data and Revised Zone Rating (RZR) at The Hardball Times. I've put the biggest movers in each category in bold.

Not such a strong sign of a 'Riggleman effect' on the fielding after two weeks. For some reason, Dunn looks good in UZR but not so good in RZR. This probably has some connection with different structures to the zones in each. I still believe that it is a mistake to consider Dunn an acceptable Major-League 1B. He does less damage in LF. However, the Nationals are committed to finding out if I'm wrong. Belliard puts up some good numbers at 2B, but that belies the evidence of last year.

Let's assess the UZR effect of trading Johnson and moving Dunn to 1B

Johnson 1B, Hernandez 2B, Dunn LF, Willingham RF  +10.6
Dunn 1B, Hernandez 2B, Willingham LF, Dukes RF    + 5.8
Dunn 1B, Belliard 2B, Willingham LF, Dukes RF     +17.3

As things stand, the Nationals are liable to be giving away half a win over 150 games with the new alignment, and Hernandez at 2B, or gaining over half a win with Belliard at 2B. Hernandez, however, appears to be the better hitter.

Player              UZR   Change  UZR/150  Change  RZR   Change   MLBaverage
Zimmerman          12.7   - 0.6    16.9     -2.5  .740   -.013     .717
Johnson           - 6.4   + 0.4   - 7.1     +0.7  .764   +.004     .785
Guzman            - 4.4   - 0.4   - 6.2     n.c.  .759   -.008     .803
Dunn (LF)         -12.4   - 0.4   -24.5     -1.4  .832   -.017     .890
Hernandez           1.0   n.c.      2.1     +0.1  .852   +.004     .815
Kearns (RF)         1.5   + 1.1     3.4     +4.5  .893   n.c.      .907
Willingham (LF)   - 1.7   - 0.4   - 5.2     -1.2  .910   +.002     .890
Harris (CF)       - 5.0   n.c.    -15.4     -0.4  .938   n.c.      .933
Dukes (CF)        - 5.6   n.c.    -20.3     +0.8  .898   n.c.      .933
Morgan (cf)         7.2   + 2.3    30.4     +3.9  .957   -.012     .933
Gonzalez (ss)     - 5.2   - 0.7   -24.7     -2.2  .692   +.004     .803
Belliard (2b)       3.3   + 1.8    13.6     -6.8  .890   +.001     .815
Willingham (RF)   - 0.6   + 0.7    -1.0     +3.4  .961   -.016     .907
Dunn (RF)         - 7.4   - 0.7   -34.6     -1.7  .761   +.005     .907
Dukes (RF)          0.5   + 0.7     3.2     +6.6  .960   +.008     .907
Gonzalez (2b)     - 1.2   + 0.7   - 9.2     +5.3  .766   -.028     .815
Dunn (1b)         - 3.5   + 0.1   -35.4     +9.1  .529   -.016     .785

The table is in order of innings played at the position, with the cut-off at 100 innings.

UZR converts fielding statistics into a +/- rating reflecting the number of runs saved or given away. There is a basic version, which is based on the number of innings played by the player, and a normalized version that assumes everybody plays 150 games. It also is forced to sum to zero, so a player can have his UZR adjusted even when he doesn't play.
RZR is like a fielding 'batting average', dividing the number of plays made by the number of opportunities. Unlike old Zone Rating, it excludes plays made 'out of zone'. (Zone Rating divides the field into zones, and assigns responsibility among the players.) For comparative purposes, I've put at the end of each player's line the MLB average RZR for position.