alternating running and jogging

Question
I'm wondering about my cardio workout. What I've been doing is walking a quarter mile, then jogging a half mile, then walking a quarter mile, then jogging a half mile and so on. I almost always do about three miles every workout. My ultimate goals are to lose weight, try and become faster as time goes on and to run a mile and a half without quitting. My questions are...

1)Is this a good workout for weightloss?
2)Are there any articles on the type of workout I'm doing that might give me some insight as to the benefits or downsides of this workout?

Answer
Hi Clay
First what your doing is ok for weight loss,but if you really want to make a big dent more rapidly,than i suggest you work up to 1 and 1/2 hours steady walking and jogging three times a week and then fill in with your normal program.There is no downside to what your doing now.It is all upside.It is the consistent efforts over time that will produce the results your looking for a long with the proper balance of nutrients.

All the best clay

John