Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: Median versus Mean Averaging
    From: Bill Lionheart
    Date: 2019 Oct 28, 09:00 +0000

    Before probing this a bit further has anyone done a literature survey
    on the distribution of errors in aeronautical sextant readings?
    At risk of stating the obvious for a random variable with a symmetric
    probability distribution the mean and mode coincide. Of course there
    is very much more to this question, starting that this is a sample
    from the distribution, but understanding the sources of the errors and
    their distribution is the first thing to do. I imaging someone did a
    study with aviators taking lots of sights from a known position!
    I looked for references when writing my paper with Moses and
    Kimberling  in the JoN (http:/dx.doi.org/10.1017/S0373463319000675)
    and found this
    Peterson, B.C. (1952). Some observations of refraction at low
    altitudes and of astronomical position-line accuracy.
    The Journal of Navigation, 5(1), 31–38.
    Shufeldt, H. (1962). Precision Celestial Navigation Experiments.
    Journal of Navigation, 15(3), 301-324.
    Gordon, R. (1964). The Attainment of Precision in Celestial
    Navigation. Journal of Navigation, 17(2), 125-147.
    (both referring to Peterson)
     I expect NavListers will know other studies, especially for
    aeronautical bubble sextants?
    On Mon, 28 Oct 2019 at 02:04, Bill Morris  wrote:
    > I'm not a mathematician and have an uncertain grasp of statistics having 
    once thought them to be a form of contact adhesive, but can say with the 
    conviction of the possibly ill-informed that taking the median ensures that 
    less weight is given to outliers.
    > And, mathematicians, how does continuously integrating as in the SOLD and 
    Hughes Marine Bubble sextant, compare with averaging sixty observations two 
    seconds apart?
    > Bill Morris
    > Pukenui
    > New Zealand
    > View and reply to this message

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site