Question 1

Discuss the disadvantages of “aggregation”

Example Answer

When we are using aggregation, the detail about the data point or micro data is ignored in order to conclude the overall picture; which is the macro level. By reducing each aspect or characteristic, it may lead to misleading conclusion.

For example, determine the performance of company (macro level) by using employee satisfaction level (micro level). Production employee will be having different satisfaction to accounting employee, aggregating regardless department would lead to neglection and causes wrong conclusion.

---

Question 2

Discuss the advantages and disadvantages of “disaggregation”

Best answer among student

---

Question 3

A model was used to determine the response time (in milliseconds) for three different types of circuits used in an automatic valve shutoff mechanism. The results are given below.

You are required to perform an analysis of variance (ANOVA) and test the hypothesis that the three circuit types have the same response time at the level of significance 5%.

Example Answer

---

Question 4

A study was conducted to evaluate three programs X, Y and Z for improving the
reading skills of Primary Six pupils. Twenty seven pupils were randomly assigned to one of three groups; each group used one of the programs. A test of reading skills was administered at the beginning and end of the school year. The dependent variable was the amount of increase from the pretest to the post test. The following data were obtained.

You are required to obtain an analysis of variance (ANOVA) table and test whether the three programs are equally effective in improving the reading skills of Primary Six pupils. Use the level of significance 5%.

Example Answer

---

Question 5

Consider the correlation between the scores on an total sales (x) and mileage claim (y). The first two columns in the table contain the identification number of the macro unit (j) which is the marketing departments for different products, and the micro-unit (i). The other two columns contain the data.

You are require to
(a) Estimate the total regression
(b) Estimate the regression between group means.
(c) Estimate the regression within groups
(d) Estimate the multilevel regression.
(e) Discuss the above four results.

Example Answer