Question

Kava is a beverage or extract that is made from Piper methysticum, a plant native to the western Pacific islands. Suppose that, in a randomized comparative experiment to determine if taking kava daily can reduce insomnia, a group of participants with insomnia were randomly assigned to take kava (treatment group) or a placebo (control group). After six weeks, the participants were interviewed to see if they experienced a decrease in insomnia. The table shows the results from the sample. The counts are the number of people in each group who experienced a decrease in insomnia. Group Description Population proportion Sample size Sample count Sample proportion 1 Treatment (kava) ?1 ?1=181 ?1=131 ?̂1=0.7238 p ^ 1 = 0.7238 2 Control (placebo) ?2 p 2 ?2=371 n 2 = 371 ?2=124 x 2 = 124 ?̂2=0.3342 p ^ 2 = 0.3342 Compute the standard error estimate, SE, of the difference in the sample proportions. Give your answer to at least four decimal places. Determine the value of the two-sample ? z ‑statistic for the difference in the two proportions, ?1−?2 p 1 − p 2 . Give your answer to at least four decimals places. SE= SE = ?= z =

Answer 1

Answer :-

- Given kava is a beverage (or) extract that is made frocus methysticum, a plant native to the western pacific islands.

- After six- weeks the participants were interviewed to see if they experienced a decrease insomnia.

* To find z value for two sample for two proportions
- Given kava is a beverage (or) extract that is made frocus methysticum, a plant native to the western pacific islands.

- After six- weeks the participants were interviewed to see if they experienced a decrease insomnia.

* To find z value for two sample for two proportions