a ABCcom posted a question on their website asking viewers to say if they

A abccom posted a question on their website asking

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a.) ABC.com posted a question on their website asking viewers to say if they approved or disapproved of the State of the Union address by the President. 33% said that they approved. Volunteer sample b.) A news reporter stood outside of Tigert (the University of Florida’s administration building) and asked all of those that exited if they thought that tuition should be increased. 100% said that tuition should be increased. Convenience sample c.) A researcher took the University of Florida phone book and chose 60 students to call using a random selection method that a computer program provided. The researcher then called each of these students. 17% of the students said that tuition should be increased. 99.7% % 68 95% 56 59 62 74 68 71 65
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Simple random sample 23. Answer the following short questions. a. What is the shape of the normal distribution? Bell/ symmetric b. What does a negative z –score tell you? That the score is below the mean c. What does a positive z-score tell you? That the score is above the mean d. What is the symbol for the mean of the Normal distribution? µ e. What is the symbol for the standard deviation of the Normal distribution? σ f. A political scientist is asking 4000 randomly selected participants if they approve of president’s performance in the past 100 days, yes or no. What is the margin of error? 1 1 = = 0.0158 n 4000 g. What is the mean and the standard deviation of the Standard Normal Distribution? Mean = 0 and Standard Deviation = 1 h. IQ scores are normally distributed with a mean of 100 and a standard deviation of 16. What is the z-score for someone who has a 90 for an IQ score? 24.The population proportion of Americans that have a gun or revolver in their home is 0.422. You randomly select 55 adults and ask them whether or not they have a gun or revolver in their homes. i) Is this problem about the sample mean or about the sample proportion? sample proportion ii) Check the conditions for the sampling distribution.
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n = 55 np 15 55(0.422) = 23.21 p = 0.422 n(1-p) 15 55(1-0.422) = 31.79 Since both conditions are met we can write the sampling distribution iii) What is the sampling distribution of the statistic? has a Normal distribution with mean equal to 0.422 and .(.) ) standard error equal to iv) Can we answer probability questions for this problem? __________________ yes _______ 25. The population proportion of Americans that are members of a church or synagogue is 0.61. You take a random sample of 50 adults and ask them whether or not they are members of a church or synagogue. i) Is this problem about the sample mean or about the sample proportion? sample proportion ii) Check the conditions for the sampling distribution. n = 50 np 15 50(0.61) = 30.5 p = 0.61 n(1-p) 15 50(1-0.61) = 19.5 Since both conditions are met we can write the sampling distribution iii) What is the sampling distribution of the statistic?
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