Reference no: EM13919644
1. Sickle-cell and malaria: Sickle-cell anemia is hereditary condition that is common among African-Americans and can cause medical problems. Some biologists suggest that the sickle-cell trait protects against malaria. That would explain why it is found in people whose ancestors originally came from Africa, where malaria is common. A study in Africa tested 523 children for the sickle-cell trait and also for malaria. Here are the results.
Severe malaria infection
Yes No
Sickle-cell trait 31 95
No sickle-cell trait 147 250
a. Estimate the proportion of severe malaria infection in those with the sickle-cell trait and those without it. In each case, provide the 95% confidence interval (CI) and interpret its value..
b. Based on the estimates and their confidence intervals, what does this tell you about the possible relationship between malaria infection and sickle-cell?.
c. Now we wish to verify whether there is an association between malaria and sickle cell using a chi-square test.
a. What are the null and alternative hypotheses for this test?
b. Find the expected cell counts under the null hypothesis. Verify that the expected counts meet the guideline for use of the chi-square test.
c. Compute the chi-square statistic and find p-value for this test.
d. What is your conclusion? Is there a good evidence of a relationship between the sickle-cell trait and severe malaria infection? Why or why not?
d. An alternative approach to evaluating the association between the outcome (severe malarial infection) and exposure (sickle-cell trait) is to test the difference of the risks (proportions) using a z-score.
a. What are the null and alternative hypotheses of this test if it was a two-tailed test?
b. What is the point estimate and its standard error?
c. Compute the test statistic and determine whether there is a significant difference in proportions using an alpha of 5%. State your conclusions and discuss how they compare to the conclusions in both (b) and (c).
Recommending controls
: You will have the opportunity in this Discussion to recommend sound internal controls over sales invoices and receivables. If controls are not in place over these functions, companies are susceptible to errors, fraud, and losses. In the following sce..
|
Z-tranforms and convolution in matlab
: Do problem 2c and 2d from homework of week 5 in Matlab.(c) and express it in positive powers of z. When computing the value of trigonometric functions, keep in mind that the arguments are always in radians and not in degrees.
|
Determine when and how this tool can be used
: Determine the feasibility of leadership solutions according to best practices for making complex and costly decisions.
|
About the current exchange rate
: In 1985, a given Japanese imported automobile sold for 1,476,000 yen, or $8,200. If the car still sold for the same amount of yen today but the current exchange rate is 144 Yen per dollar, what would the car be selling for today in U.S. dollars? Show..
|
Possible relationship between malaria infection-sickle-cell
: a. Estimate the proportion of severe malaria infection in those with the sickle-cell trait and those without it. In each case, provide the 95% confidence interval (CI) and interpret its value. b. Based on the estimates and their confidence interv..
|
What is the cost of common from reinvested earnings
: Orange Logistic is thinking of opening a new warehouse, and the key data are shown below. The company owns the building that would be used, and it could sell it for $100,000 after taxes if it decides not to open the new warehouse. No new working capi..
|
Specific application or methodological study
: In this six- to eight-page research paper, you will explore in detail one of the statistical approaches to research discussed in the course, applying it in the context of a specific application or methodological study.
|
Prepare a bus reservation system
: You will be asked to demonstrate your program to your tutor - You should be prepared to answer questions concerning your design, code and test plan.
|
Research on the classical conditioning of taste aversions
: Regarding research on the classical conditioning of taste aversions, which of the following statements is FALSE?
|