3. Extensions to Mendelian Inheritance

In analyzing genetic data, how do we know whether deviation from the expected ratio is due to chance rather than to another, independent factor?

If a chi-square test produces a chi-square value of 7.83 with 4 degrees of freedom,

Above what chi-square value would you reject the chance hypothesis for an experiment with 7 degrees of freedom?

If a chi-square test produces a chi-square value of 7.83 with 4 degrees of freedom,

Is the result sufficient to reject the chance hypothesis?