Question

In: Statistics and Probability

A political pollster is conducting an analysis of sample results in order to make predictions on...

A political pollster is conducting an analysis of sample results in order to make predictions on election night. Assuming a? two-candidate election, if a specific candidate receives at least

55?% of the vote in the? sample, that candidate will be forecast as the winner of the election. You select a random sample of 100 voters. Complete parts? (a) through? (c) below.

a.

What is the probability that a candidate will be forecast as the winner when the population percentage of her vote is 50.1%

b.

What is the probability that a candidate will be forecast as the winner when the population percentage of her vote is

58%?

Solutions

Expert Solution

(a)

Here we have

n=100 ,p = 0.501

The sampling distribution of sample proportion will be approximately normal with mean

and standard deviation

The z-score for is

So  the probability that a candidate will be forecast as the winner is

(b)

Here we have

n=100 ,p = 0.58

The sampling distribution of sample proportion will be approximately normal with mean

and standard deviation

The z-score for is

So  the probability that a candidate will be forecast as the winner is


Related Solutions

A political pollster is conducting an analysis of sample results in order to make predictions on...
A political pollster is conducting an analysis of sample results in order to make predictions on election night. Assuming a​ two-candidate election, if a specific candidate receives at least 54% of the vote in the​ sample, that candidate will be forecast as the winner of the election. You select a random sample of 100 voters. Complete parts​ (a) through​ (c) below. a. The probability is ______ that a candidate will be forecast as the winner when the population percentage of...
The main objective of a regression analysis is to make predictions of Y using X? True...
The main objective of a regression analysis is to make predictions of Y using X? True False
A political pollster wants to see if the percentage of the population that is non-white in...
A political pollster wants to see if the percentage of the population that is non-white in a state is related to the percentage of the states's votes that Barack Obama received in the 2012 presidential election. explanatory variable = x = response variable = y = Which variable is x and which variable is y?
Discuss the role of regression analysis in business by using examples of how these models might work to make predictions.
This week, we learn about regression analysis and regression “models’. Discuss the role of regression analysis in business by using examples of how these models might work to make predictions. In your discussion, consider the various components of the output and how it might be of value to understanding the data.
Describe how we can use Markov analysis to make future predictions. 200-250 word response
Describe how we can use Markov analysis to make future predictions. 200-250 word response
A Sample of coarse grained soil tested in the laboratory. The gradation analysis results are as...
A Sample of coarse grained soil tested in the laboratory. The gradation analysis results are as shown in the table below. Sieve Size (mm) Mass retained on each sieve (g) 4.75 0 2.00 40 0.850 60 0.425 89 0.250 140 0.180 122 0.150 210 0.075 56 Pan 12 Classify the soil according to Unified Soil Classification System (USCS)
The ability of models to make accurate predictions is limited by the scale of the system...
The ability of models to make accurate predictions is limited by the scale of the system to which the model is applied compared to the scale for which the model was developed. This means that predictions about plant stomate responses to water stress in a greenhouse cannot apply to a clone of the same plant growing in a massive ecosystem.   Is the above statement true or false? If false, explain why.
Suppose that 60% of registered voters support candidate A. A pollster will obtain a random sample...
Suppose that 60% of registered voters support candidate A. A pollster will obtain a random sample of 200 registered voters. What is the probability that at least 126 of the individuals in the sample support A? Do not employ a continuity correction. 0.8078 0.2447 0.1922 0.0749 0.5956
Make a set of boosted predictions on the response variable medv for the Boston dataset in...
Make a set of boosted predictions on the response variable medv for the Boston dataset in the MASS package, by first fitting the KNN model, then correcting the residuals using a singlelayer neural network with the shrinkage parameter λ = 0.1, then correcting the residuals using a random forest with shrinkage λ = 0.1. In each step, use 5-fold cross validation to tune the parameters: k (k = 5, 10, 20) in KNN, number of neurons in the hidden layer...
A random sample of 10 sales receipts for mail-order sales results in a mean sale amount...
A random sample of 10 sales receipts for mail-order sales results in a mean sale amount of $79.20 with a standard deviation of $18.75 A random sample of 16 sales receipts for internet sales results in a mean sale amount of $70.30 with a standard deviation of $28.75 Using this data, find the 98% confidence interval for the true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases. Assume that the population variances...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT