Results 1 to 3 of 3

Math Help - Hypothesis Testing

  1. #1
    Newbie
    Joined
    Dec 2010
    Posts
    7

    Hypothesis Testing

    A biologist discovers a colony of a previously unknown type of bird nesting in a cave. Out of the 16 chicks which hatch during his period of investigation, 13 are female. Test at the 5% significance level whether this supports the view that that the sex ratio for the chicks differs from 1.
    Im really stuck i think ive developed the p:H1 and p:H0 but after that i am a bit stuck any help is much appreciated thankyou
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    29
    Sounds like you should use a \displaystyle \chi^2 test here.

    \displaystyle H_0: Observed sex ratio can be described by the Expected sex ratio

    \displaystyle H_1: Observed sex ratio differs from the Expected sex ratio

    Now you need to make a table

    \begin{array}{|c|c|c|}<br />
 & \text{Male} & \text{Female}\\ \hline<br />
\text{Expected} & \dots & \dots \\ \text{Observed} & \dots & \dots \\ \chi^2_{calc} & \dots & \dots\\  \hline \end{array}

    Populate this table and find \displaystyle \chi^2_{calc} = \Sum \frac{(\text{0bserved-Expected})^2}{\text{Expected}}

    If \displaystyle \chi^2_{calc} > \chi^2_{crit}= \chi^2_{df,\alpha} reject \displaystyle H_0
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor matheagle's Avatar
    Joined
    Feb 2009
    Posts
    2,763
    Thanks
    5
    I would test that the proportion of females is .5 versus not
    Since n is small you cannot approximate with a normal and you will need to use the binomial distribution.
    You can obtain the p-value with x=13
    And n=16, p=.5.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Hypothesis testing!
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: December 8th 2009, 11:45 AM
  2. Hypothesis testing
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: October 23rd 2009, 02:53 PM
  3. Hypothesis testing
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: January 17th 2009, 01:52 PM
  4. Testing Hypothesis
    Posted in the Advanced Statistics Forum
    Replies: 3
    Last Post: January 8th 2009, 02:26 AM
  5. hypothesis testing
    Posted in the Advanced Statistics Forum
    Replies: 2
    Last Post: May 29th 2008, 12:09 PM

Search Tags


/mathhelpforum @mathhelpforum