In a certain school district, it was observed that 32% of the students in the element schools were classified as only children (no siblings).  However, in the special program for talented and gifted children, 81 out of 204 students are only children.  The school district administrators want to know if the proportion of only children in the special program is significantly different from the proportion for the school district. Test at the α=0.01α=0.01 level of significance. Using the normal approximation for the binomial distribution (without the continuity correction), was is the test statistic for this sample based on the sample proportion? z=z=  (Report answer as a decimal accurate to 3 decimal places.) You are now ready to calculate the P-value for this sample. P-value =  (Report answer as a decimal accurate to 4 decimal places.)

In a random sample of​ males, it was found that 25 write with their left hands and 217 do not. In a random sample of​ females, it was found that 58 write with their left hands and 450 do not. Use a .05 significance level to test the claim that the rate of​ left-handedness among males is less than that among females. Identify the test statistic.z=?

According to a certain government agency for a large country, the proportion of fatal traffic accidents in the country in which the driver had a positive blood alcohol concentration (BAC) is 0.38. Suppose a random sample of 105 traffic fatalities in a certain region results in 51 that involved a positive BAC. Does the sample evidence suggest that the region has a higher proportion of traffic fatalities involving a positive BAC than the country at the a = 0.01 level of significance? Because npo (1 - Po 10, the sample size is 5% of the population size, and the sample the requirements for testing the hypothesis satisfied. (Round to one decimal place as needed.) can be reasonably assumed to be random, What are the null and alternative hypotheses? is given to be random, cannot be reasonably assumed to be random, Ho: versus H,: (Type integers or decimals. Do not round.) is given to not be random, Find the test statistic, zo. Z0 = (Round to two decimal places as needed.) Find the P-value.…

A national organization that conducts research on the cost and quality of health care in the U.S. reported that, in 2012, U.S. families spent an average of $9,590 on health care expenses. Suppose you decide to test whetherthe average in 2015 is greater than the average in 2012. After conducting the appropriate statistical test, you find a P-value of 0.022. If the level of significance is 0.05, which of the following is the best interpretation of the P-value? a. The P-value of 0.022 indicates that there is a 2.2% chance that the 2015 average is greater than the average amount spent in 2012.b. The P-value of 0.022 provides weak evidence that the average in 2015 average is greater than the average amount spent in 2012.c. The P-value of 0.022 provides strong evidence that the 2015 average is greater than the average amount spent in 2012.d. The P-value of 0.022 indicates that there is a very low probability that the 2015 average is different than average amount spent in 2012.

In a random sample of males, it was found that 29 write with their left hands and 212 do not. In a random sample of females, it was found that 70 write with their left hands and 444 do not. Use a 0.01 significance level to test the claim that the rate of left-handedness among males is less than that among females. Complete parts (a) through (c) below.

In a previous poll, 39% of adults with children under the age of 18 reported that their family ate dinner together seven nights a week. Suppose that, in a more recent poll, 422 of 1145 adults with children under the age of 18 reported that their family ate dinner together seven nights a week. Is there sufficient evidence that the proportion of families with children under the age of 18 who eat dinner together seven nights a week has decreased? Use the x = 0.01 significance level. Because npo (1-Po) = 272.4 > 10 and the sample size is the hypothesis are satisfied. (Round to one decimal place as needed.) What are the null and alternative hypotheses? Ho: P = versus H₁: ▼ V (Type integers or decimals. Do not round.) Find the test statistic, Zo- C less than 5% of the population size, and the sample is given to be random, the requirements for testing Zo = (Round to two decimal places as needed.) Find the P-value. P-value = (Round to three decimal places as needed.) Is there sufficient…

The effectiveness of surgery for weight loss reported here found that "The surgery was associated with significantly greater weight loss [than the control group who dieted] through 2 years (61.3 versus 11.2 pounds, P<0.001)." What test could have been used and how would it have been computed?

n 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 25 30 35 40 45 50 60 70 80 90 100 n x=0.05 0.950 0.878 0.811 0.754 0.707 0.666 0.632 0.602 0.576 0.553 0.532 0.514 0.497 0.482 0.468 0.456 0.444 0.396 0.361 0.335 0.312 0.294 0.279 0.254 0.236 0.220 0.207 0.196 α = 0.05 α = 0.01 0.990 0.959 0.917 0.875 0.834 0.798 0.765 0.735 0.708 0.684 0.661 0.641 0.623 0.606 0.590 0.575 0.561 0.505 0.463 0.430 0.402 0.378 0.361 0.330 0.305 0.286 0.269 0.256 α = 0.01 NOTE: To test Ho: p=0 against H₁: p0, reject Ho if the absolute value of ris greater than the critical value in the table.

According to a certain government agency for a large country, the proportion of fatal traffic accidents in the country in which the driver had a positive blood alcohol concentration (BAC) is 0.34. Suppose a random sample of 109 traffic fatalities in a certain region results in 50 that involved a positive BAC. Does the sample evidence suggest that the region has a higher proportion of traffic fatalities involving a positive BAC than the country at the x = 0.01 level of significance? Because npo (1-Po) = 24.5 > 10, the sample size is (Round to one decimal place as needed.) What are the null and alternative hypotheses? p = 0.34 versus H₁: p > 0.34 Ho: p (Type integers or decimals. Do not round.) Find the test statistic, Zo. Zo = 2.62 (Round to two decimal places as needed.) Find the P-value. P-value = (Round to three decimal places as needed.) less than 5% of the population size, and the sample is given to be random, the requirements for testing the hypothesis are satisfied.

Suppose IQ scores were obtained for 20 randomly selected sets of siblings. The 20 pairs of measurements yield x=99.75​, y=101​, r=0.921​, ​P-value=​0.000, and y=2.6+0.99x​, where x represents the IQ score of the older child. Find the best predicted value of y given that the older child has an IQ of 102​? Use a significance level of 0.05.