P-value: 0.0098Area of the critical region: 0.01Critical value(s): ±2.326

[noahpww]

Use the following information to answer the questions below: A 0.01 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different than 0.5. Assume that sample data consist of 62 girls born in 100 births, so the sample statistic of 0.62 results in a z score that is 2.4 standard deviation above 0.

(a) State the null hypothesis H₀ and the alternative hypothesis H₁.(b) State the type of test: Is the test two-tailed, left-tailed, or right-tailed?

Two-tailed.

(c) What is the value of the test statistic?

Test statistic: z = 2.4

(d) Find the P-value.(e) What is the area of the critical region?(f) Find the critical value(s)?

Any help with this would be greatly appreciated!

 

[Jameson]

Hi noahpww!

I agree that this is a two-sided test. If we have a z-score and a two sided test, how do we find the area necessary to calculated a p-value. Remember that a p-value is equivalent to an area under the normal curve here, it's just a question of how to find that area. Any ideas? :)

 

[noahpww]

Do I use the invNorm feature in my calculator or the P-value Method?

 

[Jameson]

Do I use the invNorm feature in my calculator or the P-value Method?

I don't use a manual calculator these days, but yes I believe that the invNorm() function will return the area to the LEFT of a z-score. So now the question is how do we use that and our z-score to find the area of this two sided test?