Econometrics UE Past Papers Questions.

A farmer wishes to predict the number of tons of maize per acre which will result from a given number of applications of fertilizer. Data have been collected as shown in the table below:

1. Find a suitable regression relationship to help the farmer in making the required prediction
2. From your results predict the number of tons per acre resulting from 0,3,7 and 9 applications.

Answer / Solution

UNSOLVED

Suppose you are involved in a research project aiming at establishing the influence of an independent variable (XVAR) on a dependent variable (YVAR). One of your collagues is the project team member who was conversant with SPSS helped to run the analysis and produced estimation results summarized in three tables below.

SPSS output

Table 1: Model Summary

1. Predictors: (Constant), xvar

Table 2: ANOVA(b)

1. Predictors: (Constant), XVAR
2. Dependent Variable: YVAR

Table 3: Coefficients (a)

1. Dependent Variable :YVAR

Suppose this SPSS output was given to you , asnwer the following questions:

1. How many variables were dependent and how many were independent?
2. What was the explanatory power of the regression model?
3. It seems the regression model was not robust in fitting the relationship, is this true or false? If true or false explain why?
4. Was the parameter estimate for XVAR statistically significant or not? If it is significant , at what significance level (statistically plausible level is P<5%) or if it is not, explain why?
5. Suppose the YVAR is the household monthly consumption and XVAR is disposable monthly income? Discuss briefly the SPSS results of the model.

Answer / Solution

UNSOLVED

Cost of production have been monitored for some time within an agribusiness firm and the following data found:

Answer the following questions:

1. Develop mathematical and econometric models relating average total cost and production level
2. Find the regression line of average total cost on production level
3. Place the estimated regression line on the scatter plot
4. COmpute the coefficient of determination, R-Squared and interpret  it
5. Test the significance of the regression coefficient attached to independent variable (x), i.e if it is non-zero
6. Predict the average total cost if the production level were i)8500 units ii)16000 units  iii) 20000 units

Answer / Solution

UNSOLVED

To ease presentation econometric concepts are always stated using mathematical formula. State the meaning of the following formula.

Answer / Solution

UNSOLVED

Manufacturing output for palnt A and B

Using the data in the table above calculate

1. The expected output for plant A and B
2. The sample variance for plant A and B
3. Based on these output statistics which plant has a stable production? Why ?

Answer / Solution

UNSOLVED