Question

In: Statistics and Probability

A proportion, p, of people who are alcoholics is 60%. A random sample of 130 people...

A proportion, p, of people who are alcoholics is 60%. A random sample of 130 people is done, and 63 of them confused to be an alcoholic. Can we reject the hypothesis that .05 level of significance? Show work.

Expert Solution

Solution :

This is the two tailed test .

The null and alternative hypothesis is

H0 : p =0.60

Ha : p 0.60

= x / n = 63/130=0.485

P0 = 0.60

1 - P0 = 1-0.60=0.40

Test statistic = z

= - P0 / [P0 * (1 - P0 ) / n]

= 0.485-0.60/ [(0.60*0.40) /130 ]

= -2.68

P(z <-2.68 ) = 0.0038

P-value = 0.0038

= 0.05

P-value <

Reject the null hypothesis .

orchestra answered 2 years ago

A random sample of medical files is used to estimate the proportion p of all people...

A random sample of medical files is used to estimate the proportion p of all people who have blood type B. (a) If you have no preliminary estimate for p, how many medical files should you include in a random sample in order to be 85% sure that the point estimate p̂ will be within a distance of 0.06 from p? (Round your answer up to the nearest whole number.) medical files (b) Answer part (a) if you use the...

A simple random sample of 1000 elements generates a sample proportion p =0.68 a. Provide the...

A simple random sample of 1000 elements generates a sample proportion p =0.68 a. Provide the confidence interval for the population proportion (to 4 decimals). , ( , ) b. Provide the confidence interval for the population proportion (to 4 decimals). , ( , )

A simple random sample of 500 elements generates a sample proportion p = 0.72 a. Provide...

A simple random sample of 500 elements generates a sample proportion p = 0.72 a. Provide the 99% confidence interval for the population proportion (to 4 decimals). ( , ) b. Provide the 90% confidence interval for the population proportion (to 4 decimals). ( , )

1-Test the claim that the proportion of people who own cats is smaller than 60% at...

1-Test the claim that the proportion of people who own cats is smaller than 60% at the 0.05 significance level. The null and alternative hypothesis would be: A) H0:μ≥0.6H0:μ≥0.6 H1:μ<0.6H1:μ<0.6 B) H0:μ=0.6H0:μ=0.6 H1:μ≠0.6H1:μ≠0.6 C) H0:p=0.6H0:p=0.6 H1:p≠0.6H1:p≠0.6 D) H0:μ≤0.6H0:μ≤0.6 H1:μ>0.6H1:μ>0.6 E) H0:p≤0.6H0:p≤0.6 H1:p>0.6H1:p>0.6 F) H0:p≥0.6H0:p≥0.6 H1:p<0.6H1:p<0.6 The test is: A) two-tailed B) right-tailed C) left-tailed Based on a sample of 300 people, 57% owned cats The p-value is: (to 2 decimals) Based on this we:...

1) Test the claim that the proportion of people who own cats is smaller than 60%...

1) Test the claim that the proportion of people who own cats is smaller than 60% at the 0.05 significance level. The null and alternative hypothesis would be: H0:p=0.6H0:p=0.6 H1:p≠0.6H1:p≠0.6 H0:μ≥0.6H0:μ≥0.6 H1:μ<0.6H1:μ<0.6 H0:μ=0.6H0:μ=0.6 H1:μ≠0.6H1:μ≠0.6 H0:p≤0.6H0:p≤0.6 H1:p>0.6H1:p>0.6 H0:μ≤0.6H0:μ≤0.6 H1:μ>0.6H1:μ>0.6 H0:p≥0.6H0:p≥0.6 H1:p<0.6H1:p<0.6 The test is: two-tailed right-tailed left-tailed Based on a sample of 100 people, 59% owned cats The test statistic is: (to 2 decimals) The p-value is: (to 2 decimals) Based on this we: Fail to reject the null hypothesis Reject the null...

A simple random sample of 600 elements generates a sample proportion P=0.60 a. Provide the 90%...

A simple random sample of 600 elements generates a sample proportion P=0.60 a. Provide the 90% confidence interval for the population proportion (to 4 decimals). b. Provide the 95% confidence interval for the population proportion (to 4 decimals).

Assume that a random sample is used to estimate a population proportion p. Find the margin...

Assume that a random sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level. n equals 500 comma x equals 200 comma 90 % confidence The margin of error Eequals nothing. (Round to four decimal places as needed.)

The population proportion is .60. What is the probability that a sample proportion will be within...

The population proportion is .60. What is the probability that a sample proportion will be within +/- .02 of the population proportion for each of the following sample sizes? Round your answers to 4 decimal places. n=100 n=200 n=500 n=1000

1) The proportion of people at shopping mall who wear red shirts is p = 0.18....

1) The proportion of people at shopping mall who wear red shirts is p = 0.18. What is the mean of the sampling distribution given a sample size of 50? What is the standard deviation? (Central Limit Throrem). 2) What is the probability given a random sample of 50 people at shopping mall that more than 20% of them are wearing red shirts? 3) CONF. INT Suppose you take a random sample of 50 people at shopping mall and find...

it has been reported that 48% of people text and drive. A random sample of 60...

it has been reported that 48% of people text and drive. A random sample of 60 drivers is drawn. Find the probability that the proportion of people in the sample who text and drive is less than 0.498.