Questions
statistics question
In the Olympics, there are 8 swimmers in the final race. How many ways can the gold, silver, and bronze medals be distributed among the 8 contestants?
In: Statistics and Probability
Statitics
A researcher wants to determine the association between two continuous variables, X and Y. A sample of 100 individuals were taken from a population where the values of X and Y were measured from each individual.
a) The correlation coefficient of X and Y were calculated from this sample and the value is 0.2, what is the implication of this value?
b) What may go wrong if the researcher concludes on the association between variables X and Y based on only the correlation coefficient?
c) What should the researcher do to avoid the mistake that might occur in part(b)?
In: Statistics and Probability
Which value shows that a statistic is significant under normal assumptions.
Which value shows that a statistic is significant under normal assumptions.
In: Statistics and Probability
Heteroskedasticity in OLS estimators has several consequences.
Heteroskedasticity in OLS estimators has several consequences. State and explain the consequences.
In: Statistics and Probability
Regression Analysis
Briefly explain steps that are required to run a regression on a specific model
In: Statistics and Probability
If the MGF of x is Mx(t)=(0.6e^t+0.4)^8.Find variance?
Moment generating functions
In: Statistics and Probability
Determine the point estimate of the population proportion, the margin of error for the following confidence interval
Determine the point estimate of the population proportion, the margin of error for the following confidence interval, and the number of individuals in the sample with the specified characteristic, x, for the sample size provided.
Lower bound=0.226,upper bound=0.604,n=1200
The point estimate of the population is? round to the nearest thousandth as needed.
the margin error is? round to the nearest thousandth as needed.
the number of individuals in the sample with the specified characteristic is? round to the nearest integer as needed.
In: Statistics and Probability
To test the Ho: u = 40 versus Hi: u < 40, a random sample of size n = 26 is obtained from a population that is known to be normally distributed.
To test the Ho: u = 40 versus Hi: u < 40, a random sample of size n = 26 is obtained from a population that is known to be normally distributed. Complete (a) through (d).
if x = 36.8 and s = 13.9, compute the test statistic.
to = ??? (round to three decimals as needed)
a) ta = ??? (round to three decimal places. Use a comma to separate answers)
b) If the researcher decides to test this hypothesis at the a = 0.1 level of significance, determine the critical value(s). Although technology or a t-distribution table can be sued to find critical value, in this problem use the t-distribution table given.
c) Draw a t-distribution that depicts the critical region.
d) Will the researcher reject the null hypothesis?
Yes because the test statistic falls in the critical region
Yes because the test statistic does not fall in the critical region
No because the test statistic does not fall in the critical region
In: Statistics and Probability
Construct the indicated confidence interval for the difference between the two population means.
Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. Independent samples from two different populations yield the following data. The sample size is 478 for both samples. Find the \(85 \%\) confidence interval for \(\mu_{1}-\mu_{2}\).
\(\bar{x}_{1}=958, \bar{x}_{2}=157, s_{1}=77, s_{2}=88\)
A. \(800<\mu_{1}-\mu_{2}<802\)
B. \(791<\mu_{1}-\mu_{2}<811\)
C. \(793<\mu_{1}-\mu_{2}<809\)
D. \(781<\mu_{1}-\mu_{2}<821\)
In: Statistics and Probability
A nurse measured the blood pressure of each person who visited her clinic.
A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40. The blood pressure readings were given to the nearest whole number. Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading between 110 and 119 inclusive?
In: Statistics and Probability
The following graph represents the results of a survey, in which a random sample of adults in a certain country was asked if a certain action was morally wrong in general.
The following graph represents the results of a survey, in which a random sample of adults in a certain country was asked if a certain action was morally wrong in general. Complete parts (a) through (c).
(a) What % of the respondents believe that the action is morally acceptable? (round to nearest whole number as needed)
(b) If there are 217 adults million adults in the country, how many believe that the action is morally wrong? (round to nearest million as needed)
(c) If a polling organization claimed that the results of the survey indicate that 9% of adults believe that the action is acceptable in certain situations, would you say this statement is descriptive or inferential? Why?
In: Statistics and Probability
in a relative frequency distribution, what should the relative frequencies add up to?
in a relative frequency distribution, what should the relative frequencies add up to?
In: Statistics and Probability
About what proportion of college women are between 65 and 67 inches tall?
Heights of college women have a distribution that can be approximated by a normal curve with a mean of 65 inches and a standard deviation equal to 3 inches. About what proportion of college women are between 65 and 67 inches tall?
- A. 0.17
- B. 0.50
- C. 0.25
- D. 0.75
In: Statistics and Probability