Which decomposition relates total variation of Y into explained and unexplained parts in regression?

Correct answer: SST = SSR + SSE (sum of squares total equals regression plus error)

Explanation

ANOVA decomposition in regression: total sum of squares equals explained plus unexplained variation (chapter ANOVA table).

Other questions

Question 1

Which sampling method guarantees that every member of a population has an equal chance of selection?

Question 2

You want the standard error of a sample mean to be at most 0.5 units. If the population standard deviation is estimated to be 4.0, what minimum sample size n do you need (use the population formula)?

Question 3

Which statement best describes the central limit theorem as used for sample means?

Question 4

An analyst has a sample of n = 25 independent observations from a population with unknown variance. The sample mean is 10 and the sample standard deviation is 5. What is the estimated standard error of the sample mean?

Question 5

Which sampling method is most appropriate when you need to ensure representation across known subgroups (for example, bond duration buckets) and to improve precision?

Question 6

An analyst has a sample of 50 returns and computes a 95 percent confidence interval for the mean. Which significance level alpha corresponds to this interval?

Question 7

Which statement about bootstrap resampling is true?

Question 8

You compute a t-statistic of 2.5 with df = 20 for a two-sided test. Which statement is correct at alpha = 0.05?

Question 9

An analyst wants to test whether two independent samples have equal means and assumes equal variances. What test should she use?

Question 10

What is the formula for an expected cell frequency Eij in a contingency table under the null hypothesis of independence?

Question 11

Which of the following is a valid reason to use a nonparametric test instead of a parametric t-test?

Question 12

When performing a bootstrap with B resamples to estimate the standard error of a statistic theta_hat, which expression gives the bootstrap standard error estimate?

Question 13

You test H0: sigma^2 = 0.04 for a normally distributed variable using a sample of n = 16 and obtain sample variance s^2 = 0.02. Which test statistic should you use?

Question 14

Which of the following best describes a Type I error in hypothesis testing?

Question 15

An analyst uses a two-sample t-test with pooled variance and obtains a p-value of 0.03. At alpha = 0.05 what should she conclude?

Question 16

Which test is appropriate to examine whether the variance of returns changed after a policy event using two independent samples (before and after) of normally distributed returns?

Question 17

A researcher has a single sample of size n = 12 of monthly returns and wishes to estimate the standard error of the sample median but no analytic formula is available. Which method is most appropriate?

Question 18

Which of the following is the correct test statistic to test whether a sample Pearson correlation r differs from zero for n observations?

Question 19

Which approach is best if you have ranked (ordinal) performance scores for fund managers and you want to test whether two groups have different central tendency?

Question 20

You observe two time periods with very different volatilities in a regression residual plot, indicating heteroskedasticity. Which statement is true?

Question 21

In a simple linear regression Y = b0 + b1 X + e, what is the meaning of b1?

Question 23

In simple linear regression, how is the coefficient of determination R^2 related to the sample correlation r between X and Y?

Question 24

You estimated a simple regression with n = 30 observations and obtained SSR = 45 and SSE = 155. What is R^2?

Question 25

In regression output, the F-statistic tests which null hypothesis for a simple linear regression?

Question 26

Which regression assumption is violated if residuals plotted against time display a clear seasonal pattern?

Question 27

You run a simple regression Y on X and obtain slope b1_hat = 0.8, se(b1_hat) = 0.2, n = 25. What is the t-statistic to test H0: b1 = 0?

Question 28

Which transformation yields a model where the slope approximates an elasticity (percent change in Y per percent change in X)?

Question 29

If residuals of a regression are not normally distributed but the sample size is very large, what does the chapter recommend regarding inference?

Question 30

Which of the following is an advantage of cluster sampling relative to simple random sampling?

Question 31

An analyst computes sample correlation r = 0.3 with n = 12. Using t = r sqrt((n - 2)/(1 - r^2)), what is the approximate t-statistic (round to two decimals)?

Question 32

Which of the following correctly describes the jackknife resampling method?

Question 33

If a regression's residuals have a mean not equal to zero, what does the chapter say about that result?

Question 34

Which of these is a correct expression for the standard error of the forecast for a new Xf in SLR (prediction standard error)?

Question 35

Which functional transformation would you try if plotting Y versus X shows curvature suggesting exponential growth of Y?

Question 36

Which of the following is TRUE about the relationship between the t-test for slope and the F-test of overall fit in a simple linear regression?

Question 37

Which of the following best describes the purpose of a paired (dependent) samples t-test?

Question 38

A contingency table has 4 rows and 3 columns. What are the degrees of freedom for the chi-square test of independence?

Question 39

Which statement about the bootstrap and jackknife methods is consistent with the chapter?

Question 40

You conduct a chi-square test of independence on a 3x3 contingency table and obtain chi-square statistic = 12.5. The critical value at alpha = 0.05 with df = 4 is 9.49. What is your decision?

Question 41

When is the pooled variance estimator used in two-sample t-tests?

Question 42

You construct a 95 percent prediction interval for an SLR forecast and find it wide. According to the chapter, which factor would contribute MOST to the interval width?

Question 43

Which of the following is an example of non-probability sampling?

Question 44

When comparing means for two dependent samples, which distribution does the test statistic follow under normality assumptions?

Question 45

An analyst performs stratified sampling with k strata and samples proportional to stratum sizes. Which effect does stratification typically have compared with simple random sampling of the same overall sample size?

Question 46

Which of the following best describes the p-value reported by software for a regression coefficient?

Question 47

Which of the following is NOT an advantage of bootstrap resampling mentioned in the chapter?

Question 48

If you want to test whether two categorical classifications are independent using a sample of 1,000 observations in a 2x3 table, which test and degrees of freedom are appropriate?

Question 49

Which diagnostic plot is most helpful to detect heteroskedasticity in a regression model?

Question 50

Which of these is a correct interpretation of an R^2 value of 0.80 in a simple linear regression of ROA on CAPEX, as illustrated in the chapter example?