Assuming that the residuals are normally distributed, the estimated variance of the error terms has the
following sampling distribution under SLR: - Chi-square with n-2 degrees of freedom
fitted values def - the regression line with parameters replaced with the estimated regression
coefficients
...
ISYE 6414 Midterm Summer Study Guide
| 2024 Questions & Answers | 100%
Correct | Verified
Assuming that the residuals are normally distributed, the estimated variance of the error terms has the
following sampling distribution under SLR: - ✔✔Chi-square with n-2 degrees of freedom
fitted values def - ✔✔the regression line with parameters replaced with the estimated regression
coefficients
the estimators of the linear regression model are derived by - ✔✔minimizing the sum of squared
differences between observed and expected values of the response variable
the estimators for the regression coefficients are - ✔✔unbiased regardless of the distribution of the data
data
the assumption of normality is needed for - ✔✔the sampling distribution of the estimators of the
regression coefficients and hence for inference
the estimated versus predicted regression line for a given x* have - ✔✔the same expectation
the variability in the prediction comes from - ✔✔the variability due to a new measurement and due to
estimation
residual analysis is used for - ✔✔assessing uncorrelated errors; goodness of fit assessment
we detect departure from the assumption of constant variance - ✔✔when the residuals increase as the
fitted values increase (or decrease, etc)
, There is a direct relationship between the coefficient of determination and the correlation between the
predicting and response variables (T/F) - ✔✔True
The coefficient of determination is interpreted as - ✔✔the percentage of variability in the response
variable explained by the model
Box-Cox transformation is commonly used to improve upon the linearity assumption (T/F) - ✔✔FALSE
If a departure from independence assumption is detected, we transform the response variable to
improve assumption (T/F) - ✔✔FALSE
pooled variance estimator is - ✔✔the variance estimator assuming equal variances
total sum of squares / N-1 = - ✔✔the sample variance estimator assuming equal means and equal
variances
MSE measures - ✔✔the within-treatment variability
if we reject the test of equal means, we conclude - ✔✔that some treatment means are not equal
objective of pairwise comparison - ✔✔to identify the statistically significantly different means
estimated SLP coefficient beta zero measures strength of linear relationship between predicting and
response variables (T/F) - ✔✔FALSE - beta zero is intercept
in SLR, we lose three degrees of freedom when estimating the variance of the error terms (T/F) -
✔✔FALSE - we lose two degrees of freedom because variance estimator only uses estimates for beta
zero and beta one in its calculation
sampling distribution of the estimator of the variance is ____ distributed with ____ degrees of freedom -
✔✔chi-squared, n-2 (under assumption of normality of error terms)
Voordelen van het kopen van samenvattingen bij Stuvia op een rij:
Verzekerd van kwaliteit door reviews
Stuvia-klanten hebben meer dan 700.000 samenvattingen beoordeeld. Zo weet je zeker dat je de beste documenten koopt!
Snel en makkelijk kopen
Je betaalt supersnel en eenmalig met iDeal, creditcard of Stuvia-tegoed voor de samenvatting. Zonder lidmaatschap.
Focus op de essentie
Samenvattingen worden geschreven voor en door anderen. Daarom zijn de samenvattingen altijd betrouwbaar en actueel. Zo kom je snel tot de kern!
Veelgestelde vragen
Wat krijg ik als ik dit document koop?
Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.
Tevredenheidsgarantie: hoe werkt dat?
Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.
Van wie koop ik deze samenvatting?
Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper hussle. Stuvia faciliteert de betaling aan de verkoper.
Zit ik meteen vast aan een abonnement?
Nee, je koopt alleen deze samenvatting voor $7.99. Je zit daarna nergens aan vast.