rider

n.

骑手，骑马的人，善于骑马的人，骑师；（精密天平上的）游（动砝）码；附文，附加条附加条款款；扶手

复数：riders

free rider搭便车者；免费享用公共货物者

1. In the far distance I saw a rider approaching.
   在远处，我看见一位骑士渐渐靠近。
2. The rider forced his horse on through the storm.
   骑士迫使他的马在暴风雨中前进。

The free rider problem: Experimental evidence
Takeover Bids, The Free-Rider Problem, and the Theory of the Corporation
Institutions and the Free Rider: The Assurance Problem in Collective Action
Optimal Allocation of Public Goods: A Solution to the "Free Rider"Problem
The Chromosomal Passenger Complex (CPC): From Easy Rider to the Godfather of Mitosis
Constructive Intergroup Competition as a Solution to the Free Rider Problem: A Field Experiment
Indirect reciprocity can stabilize cooperation without the second-order free rider problem.
Experiments on the provision of public goods: Resources, interest,group size and the free rider problem
Experiments on the Provision of Public Goods. I. Resources, Interest, Group Size, and the Free-Rider Problem
Experiments on the Provision of Public Goods. II. Provision Points, Stakes, Experience, and the Free-Rider Problem