Finding Critical Values of χ2 For large numbers of degrees of freedom, we can approximate critical values of χ2 as follows:
Here k is the number of degrees of freedom and z is the critical value(s) found from technology or Table A-2. In Exercise 12 “Spoken Words” we have df = 55, so Table A-4 does not list an exact critical value. If we want to approximate a critical value of X2 in the right-tailed hypothesis test with α = 0.01 and a
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ELEMENTARY STATISTICS
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