A general overview of post trial activity among litigants in tort and contract trials concluded in the nation’s 75 most populous counties . . . [shows that] litigants requested post trial relief in an estimated 28% of civil trials [31% of cases where the plaintiff wins, and 25% of cases where the plaintiff lost] and filed notices of appeal in 18% of civil trials. Post trial motions were filed in nearly a third oftrials won by the plaintiff and in a quarter of trials where the plaintiff did not prevail. In terms of appellate activity, appeals were filed at nearly identical rates among trials won (18%) and lost (17%) by the plaintiff. . . .[There is] post trial activity taking place in a sizeable minority of civil trials concluded in the nation’s 75 most populous counties. Among the civil trials examined, litigants filed either a post trial motion or an appeal in over a third (35%) of civil trials decided in 2005. . . .
Defendants who lost at trial filed post trial motions (22%) at levels that were only somewhat higher compared to their plaintiff counterparts (14%). Wider discrepancies between plaintiffs and defendants were apparent concerning the filing of an appeal. Defendants (15%) were nearly three times as likely to file an appeal as plaintiffs 6%) in civil trials where the jury or judge found for the plaintiff. . . . Over a third (37%) of plaintiff winners requesting post trial relief received it. Defendants, in comparison, were granted post trial relief in 1 out of  trials where they sought to amend or overturn trial decisions that found for the plaintiff. . . .
Not surprisingly, plaintiffs filed post trial motions (21%) and appeals (16%) in considerable numbers of trials that they lost. Defendant winners, in comparison, sought post trial relief by filing motions or appeals in less than 5% of civil trials. In terms of ruling in favor of a post trial motion, courts granted post trial relief to only 7% of plaintiffs who sought it. Even though few defendants who won at trial requested relief, it was granted to [58%] of those defendants making a relief request. . . .
Both plaintiffs and defendants were significantly more likely to seek post trial relief in jury compared to bench trials. . . .
The predicted probability of plaintiff winners filing post trial motions ranged from 9% for rental lease cases to 21% for product liability cases. Plaintiffs prevailing at trial were also predicted to file post motions in over 15% of professional (19%) and medical malpractice (18%) cases.
Over half of defendants who lost at trial were predicted to seek post trial relief in product liability (55%), medical malpractice (56%), employment discrimination (59%), and professional malpractice cases (61%). In comparison, an estimated 16% of defendant losers in automobile accident cases were predicted to file post trial motions. . . .
Plaintiff losers were predicted to request post trial relief in over 30% of other contracts (31%) and fraud (38%) cases. The probability of plaintiff post trial behavior also exceeded 25% in intentional tort, product liability, and professional malpractice cases.
For defendants who won at trial, the predicted probabilities of post trial relief motion activity ranged from 1% in product liability cases to 10% in professional liability and rental lease cases.
From here (sample size 10,490 trials; plaintiff won 5,682 and plaintiff lost 4,808; real estate trials and trials in small counties were excluded from the sample).
Motions to modify awards in civil cases are much more often granted than requests to make a ruling notwithstanding a jury verdict, or to grant a new trial. Unsurprisingly cases with higher stakes are more likely to be contested, while results more satisfactory to a party are less likely to be contested by that party.