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Confidence Level for Microwave Detector

Confidence Level for Microwave Detector

(OP)
I have studied some statistics in my electrical engineering and physics classes but not enough to know or cover what "95% confidence level" is and how to apply it.
I need help for the following task:
Our traffic department needs to determine the "95% confidence level" of a microwave detector.  It will be installed at a city intersection with in-the-street magnetic loops to detect cars approaching or waiting for the traffic light to change.  The point is to determine whether or not the microwave detector is reliable enough under conditions of rain, fog, heat, cold, day or night conditions to replace expensive in-the-street loops.  The microwave detector will be aimed at a lane that has a loop for its evaluation and the counts of the microwave detector compared to the loop counts.  My boss needs to know how many vehicle counts are required to get this "95% confidence."  The loop detectors will count all vehicles while the microwave detector may or may not detect all vehicles under all the above conditions.
Thank you in advance for any help.
Alan

RE: Confidence Level for Microwave Detector

On it's simplest terms, whether it meets the 95% confidence interval can be merely calculated as the percantage of positive results when compared to the loop detector.  If it is above 95% you are OK.

If you get a large number of samples, then statistically, you will be very close to the true result (Population).  If you have a small sample size you will need to start looking at sample statistics versus population statistics.

Of importance though, is when the 5% of scenarios occur.  If they are random, then the system should be acceptable, but if they all occur under certain conditions, then the whole system will not function at times.  This would be unnacceptable for that type of system.

Craig

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