Data Analysis and Modelling

This is the question set along with answers Data Analysis and Modelling Fall 2017, which was taken by the Pokhara University.

Pokhara University – Data Analysis and Modelling Fall 2017

Section "A"

Very Short Answer Questions

Attempt all the questions.

1. Draw the network diagram of project plan.
   
2. Define multi-collinearity.
3. Explain about dummy variable.
4. What are the components of time series?
5. Scatter diagram below shows the relationship between number of vehicles and number of road deaths in ten countries. Compute the correlation coefficient between vehicle numbers and road deaths and comment upon the possible relationship between the two variables.
   
6. A large school district is reevaluating its teachers' salaries. They have decided to use regression analysis to predict mean teacher salaries at each elementary school. The research has come up with the following quadratic regression equation:
   Experience of teacher. If teacher has 8 years of experience, what is the expected salary?
7. You are performing a simple linear regression analysis from your sample of n=18, t a 95% confidence interval estimate of the population slope β1.
8. Enrollment in a particular class for the last four semesters has been 120, 126, 110, and 130. Suppose a one-semester moving average was used to forecast enrollment (this is sometimes referred to as a naïve forecast). Thus, the forecast for the second semester would be 120, for the third semester it would be 126, and for the last semester it would be 110. What would the MAD be for this situation?
9. If ∑P0Q0=1600, ∑P0Q1=1725, ∑P1Q0=2042, ∑P1Q1=2185. Does Fisher`s index satisfies factor reversal test? Explain.
10. Demand for an item is given as follows: calculate the forecast value using 3 years moving average?
    

    Section "B"

    Descriptive Answer Questions

    Attempt any six questions

11. The managers of a brokerage firm are interested in finding out if the number of new clients a broker brings into the firm affects the sales generated by the broker. They sample 10 brokers and determine the number of new clients they have enrolled in the last year and their sales amounts in thousands of dollars. These data are presented in the table that follows:
    
    Calculation Shows that:
    ΣX = 260 ΣY = 480ΣX² = 7594 ΣY² = 24276ΣXY = 13377 SSX=834
    SST = 1236 SSE = 271.241
    Referring to SCENARIO B1, answer the following questions:
    a) State the regression equation and interpret the meaning of slope in this problem.
    b) Compute the coefficient of determination and interpret it.
12. The demand for patient surgery at Washington General Hospital has increased steadily in the past few years as seen in the following table.
    
    The director of medical services predicted six years ago that demand in year 1 would be 42 surgeries (i.e. F1 = 42). Using exponential smoothing technique with a smoothing constant of = 0.2, develop a forecast for year 2 through 6. Also, compute the MAD and MAPE