Question: When a 9-year-old does not take the trash out he is forced to give up his video game for a week. Is this an advisable parenting strategy?
Answer: I don't think that's an advisable parenting strategy for a few reasons, let me explain why. This is a form of behavioral treatment, which is good. We do this all of the time both in positive and negative veins. We'll give kids rewards if they do well. We might take things away from kids if they do something that we'd rather them not do. But for these interventions to be most effective, it's helpful if the intervention matches up with the thing that they did that you didn't want. Taking the trash out has nothing to do with having the video game taken away.
What you might instead do is say, "Tomorrow we're going to collect the trash around the neighborhood. That's going to be the consequence for your not having taken the trash out yesterday." You can even have fun doing it. You can make it into a community-service type activity, but what it does is tie the consequences of the action to the behavior that you're trying to change. I think that's a much more effective means of changing the behavior then simply taking away something that has nothing to do with the activity.
The final thing I might add is it's awful hard to take a video game away for a week so you want to be wary of a consequence that you can't enforce. Most kids have a means of getting at those video games despite the desire to take them away.