g3 Flashcards
Response Variable.
dependent variable
Unexplained Responses.
error
Explanatory Variable.
Independent Variable
Line used to represent the relationship between response and explanatory
variable
. Linear Relationship
A mathematical representation (or mathematical model) of observed data.
Statistical Model
What is the purpose of a simple linear regression model?
C) To predict values of an output variable based on an input variable
What is the definition of the slope in linear regression?
D) The change in the response variable for a unit change in the explanatory variable
What effect does adding an additional explanatory variable to a linear regression have on the
slope of the original variable?
D) It increases the slope of the original variable
If the slope of a linear regression is 2, what does it mean?
For a unit increase in the explanatory variable, the response variable increases by 2
If the slope of a linear regression is negative, what can we say about the relationship between
the explanatory and response variables?
B) There is a negative relationship
If two variables have a positive association, the slope is
positive
If two variables have a negative association, the slope is
negative
if two variables are not associated, then the slope is
0 (and the line is horizontal)
The point where the line or curve crosses the axis of the graph.
Intercept
a measure of its steepness.
Slope
The best way to find violations and errors is to examine the plot themselves.
t orr f
true
The regression line can be plotted anywhere on the graph even at points when it
doesn’t make sense.
true or false
false
Violations against normality mainly revolves around errors when it comes to the
normal distribution of plotted data.
true
You can transform the formula of some variables in the software you are using in
case that your data is not linear.
true
An outlier does not affect the appearance of the graph at all.
false
A term given to a data that lies outside the normal expected data pattern.
Outlier
The type of error which refers to the rejection of a null hypothesis that is actually true in
the population.
type 1 error
The violation concerned with the independent variables and samples used.
b. Violation against Independence
The concept which assures that the values of the samples received doesn’t affect other
samples.
independence
Graphs that present the relationship between two variables of data using a
two-dimensional plane/cartesian coordinate system to represent the data.
Scatterplot
The state of data wherein the samples collected follow the normal distribution pattern
when plotted.
Normality
The concept which refers to the inclination of two or more variables to change at the
same rate, which when plotted, shows a straight line.
Linearity
The probability that the null hypothesis will be rejected.
Power
The sample size of a hypothesis test depends on these two factors.
Power and
Type 1 error.Power and
Type 1 error.
- It is a crucial step in identifying and solving the main problem of the study.
Describing the Data
a graph that presents the relationship between two variables of the data.
C. Scatter Plot
used by scatter plots to represent the data.
Two-Dimensional Plane
- Scatter plots are used as a _________________.
Graphical Summary
What can be seen on the horizontal axis of a scatter plot?
Independent Variable
What can be seen on the vertical axis of a scatter plot?
B. Dependent Variable
is a measure between two variables of how much one variable changes when the other
variable changes.
Association
- If one variable increases as the other variable increases, the association is ___________.
Positive
- If one variable decreases as the other variable increases, the association is
negative
- What do you call the point in a scatter plot?
observation
is a statistical measure that describes the relationship between two variables.
A. Correlation
- Correlation is used as a ___________.
C. Numerical Summary
This is the numerical value of correlation that indicates a perfectly positive relationship
between two variables.
A. +1
- This is the numerical value of correlation that indicates no relationship between two
variables.
B. 0
- This is the numerical value of correlation that indicates a perfectly negative relationship
between two variables.
C. -1
True or False: The regression formula represents the relationship between the dependent and
independent variables.
True
True or False: The prediction equation is used to estimate the value of the dependent variable
based on the values of the independent variables.
True
True or False: Heteroscedasticity is a violation of the assumption that the variance of the error
terms is constant across all levels of the independent variables.
True
True or False: In a regression model, the coefficients represent the average change in the
dependent variable for a one-unit change in the independent variable, holding other variables
constant.
True
True or False: The Ordinary Least Squares (OLS) method is used to estimate the coefficients in a
linear regression model.
True
True or False: If heteroscedasticity is present in a regression model, the standard errors of the
coefficients can be biased.
True
True or False: Transforming variables (e.g., taking the logarithm) is a common technique for
addressing heteroscedasticity.
True
True or False: Weighted Least Squares (WLS) is a regression technique that can be used to
correct for heteroscedasticity.
True
True or False: A scatter plot of residuals against predicted values can be used to visually detect
heteroscedasticity.
True
- True or False: The Breusch-Pagan test is a statistical test used to formally detect
heteroscedasticity.
True
True or False: Heteroscedasticity always leads to biased coefficient estimates in a regression
model.
False
True or False: If heteroscedasticity is detected, it is always necessary to take corrective action
before interpreting the regression results.
False
True or False: Robust standard errors are used to correct the standard errors in cases of
heteroscedasticity.
True
True or False: In some cases, heteroscedasticity may not significantly affect the validity of the
regression results, especially when the sample size is very large.
True
True or False: The Goldfeld-Quandt test is a statistical test used to formally detect
heteroscedasticity.
True