In: Math
In a study of 1910 schoolchildren in Australia, 1050 children indicated that they normally watch TV before school in the morning. (Interestingly, only 35% of the parents said their children watched TV before school!)
(a)
Construct a 95% confidence interval for the true proportion of Australian children who say they watch TV before school. (Round your answers to three decimal places.)
(_____,________)
What assumption about the sample must be true for the method used
to construct the interval to be valid?(b)
The 1910 schoolchildren used in the study formed a random sample from the population of children in Australia who normally watch TV before school in the morning.
The 1050 children who indicated that they normally watch TV before school in the morning formed a random sample from the population of schoolchildren in Australia.
The 1910 schoolchildren used in the study formed a random sample from the population of schoolchildren in Australia.
The 1050 children who indicated that they normally watch TV before school in the morning formed a random sample from the population of children in Australia who normally watch TV before school in the morning.
Since we are testing for school chidren who told they watched tv before school we will use the proportion of children who indicated they watch tv and not what their parents said
This is confidence interval for true binomial proportion
95% Confidence interval for true proportion is
= 1.96 Using normal probabilities tables
b.
What assumption about the sample must be true for the method used to construct the interval to be valid?(b)
The 1910 schoolchildren used in the study formed a random sample from the population of children in Australia who normally watch TV before school in the morning.
The 1050 children who indicated that they normally watch TV before school in the morning formed a random sample from the population of schoolchildren in Australia.
The 1910 schoolchildren used in the study formed a random sample from the population of schoolchildren in Australia
We want that the entire sample under study should be random not just the proportion.
The 1050 children who indicated that they normally watch TV before school in the morning formed a random sample from the population of children in Australia who normally watch TV before school in the morning.