Question

80. Research commissioned by AT&T and conducted by Braun Research in 2015 polled 2,067 people in the U.S. aged 16-65 who use their smartphone and drive at least once a day. An unsettling 17% of the respondents admitted to taking pictures/selfies while driving. (a) What is the point estimate for the proportion of drivers who take pictures with a smartphone while driving? b) what is the multiplier for a 90% co nfidence interval to estimate the proportion of drivers who take photos? (c) What is the standard error for the proportion who take photos? (d) What is the margin of error? (e) Construct a confidence interval for proportion of all drivers who take pictures while driving. (f) Interpret the interval. (g) A friend claims that 25% of drivers take pictures while behind the wheel? Is your friend's claim valid? Explain. 81. Research commissioned by AT&T and conducted by Braun Research in 2015 polled 2,067 people in the U.S. aged 16-65 who use their smartphone and drive at least once a day. When asked if they used Facebook while driving, 558 respondents answered "yes". (a) What is the point estimate for the proportion of drivers who access Facebook while driving? (b) what is the margin of error for a 95% confidence interval? (c) Construct a confidence interval for proportion of all drivers who take pictures while driving. (d) Interpret the interval. e) An independent researcher claims that 30% of drivers use Facebook behind the wheel. Based on the interval, is the claim valid? Explain.

Answer 1

80-a) the point estimate for the proportion of drivers who take pictures with a smartphone while driving is 17%=0.17

b) Multiplier for a 90% confidence interval is 1.645

c) standard error is sqrt(p*q/n)= sqrt(0.17*0.83/2067)= 0.0083

d) Margin of error= 1.645*0.0083= 0.01365

e) 90% confidence interval is

$p\pm MOE$

$0.17\pm 0.01365$

(0.15635,0.18365) is 90% confidence interval.

f) You can be 90% confident that the true population proportion (p) falls between (0.15635,0.18365)

g) Since 90% confidence interval does not contain 0.23 so we can say that my friends claim is valid.

NOTE: PLEASE REPOST QUESTION 81 Thank you.