Statistics

41. To test the equality of variances of two independent normal populations, we use:

• A Z-test
• B t-test
• C Chi-Square test
• D F-test Correct answer

42. The critical region is also known as the:

• A Acceptance region
• B Rejection region Correct answer
• C Confidence interval
• D Significance level

43. A hypothesis that completely specifies the distribution is called a:

• A Simple hypothesis Correct answer
• B Composite hypothesis
• C Null hypothesis
• D Alternative hypothesis

44. The p-value is the probability of obtaining a test statistic at least as extreme as the one observed, assuming:

• A H0 is false
• B H0 is true Correct answer
• C H1 is true
• D Alpha is 0.05

45. The value of the correlation coefficient (r) always lies between:

• A 0 and 1
• B -1 and 1 Correct answer
• C -infinity and +infinity
• D -1 and 0

46. If the correlation coefficient between X and Y is zero, it implies:

• A No relationship exists
• B No linear relationship exists Correct answer
• C A perfect positive relationship exists
• D X and Y are independent

47. The coefficient of determination is equal to:

• A r
• B r^2 Correct answer
• C 1 – r^2
• D sqrt(r)

48. In a simple linear regression equation Y = a + bX, 'b' represents the:

• A Y-intercept
• B Slope of the regression line Correct answer
• C Correlation coefficient
• D Standard error

49. If both regression coefficients b_yx and b_xy are negative, the correlation coefficient 'r' must be:

• A Positive
• B Negative Correct answer
• C Zero
• D Undefined

50. The geometric mean of the two regression coefficients (b_yx and b_xy) is equal to:

• A The correlation coefficient r Correct answer
• B The coefficient of determination r^2
• C The standard error
• D The intercept a