Two groups of students (males and females) were examined in Statistics for Decision Making course. The following were the scores obtained by the males and females samples consisting of ten students each:
Group A (Males): 60, 44, 43, 77, 80, 98, 68, 67, 60, 48
Group B (Females): 12, 55, 80, 68, 75, 50, 32, 90, 56, 42
i. For each group, calculate the mean score and interpret your result. (3 marks)
ii. Which group had varied scores? (4 marks)
Traditionally, the demand for Kakabo Local Rice is determined by a number of factors. An economist has collected data on few of these factors and has estimated their contribution to the purchase behavior of customers. The tables below indicate the regression output of the quantity of 5kg bag of Kakabo Local Rice. Use the information in the tables to answer the questions that follow:
Regression Statistics
Multiple R: 0.9965
R Square
Adjusted R Square
Standard Error: 0.5332
Observations: 21
ANOVA
Df SS MS F Significance F
Regression 4 653.761 163.440 574.928 0.000
Residual 16 4.548 0.284
Total 20 658.310
Coefficients Standard Error t Stat P-value Lower 95% Upper 95%
Intercept 9.104 7.352 1.238 0.233 -6.481 24.689
Price 0.137 -2.239 0.040 -0.599 -0.016
Income 0.267 0.127 0.051 -0.001 0.535
Taste 0.636 2.357 0.032 0.064 1.208
Population -0.050 -0.223 -0.527 0.427
i. State and explain the estimated equation for the 5kg bag of rice. (4 marks)
ii. What percentage of the variation is not explained by the exogenous (independent) variables? (1 mark)
iii. Which of the independent variable(s) is/are significant in explaining the changes in quantity of rice and why? (2 marks)
iv. If price changes by 1 unit, state the range of values within which quantity will fall for 95% confidence level. (1 mark)