MATH 225N WEEK 8 ASSIGNMENT LINEAR
DEPENDENCE REVIEW SHEET 2026 FULL
EXPLANATION PROVIDED
◉ Which variable ALWAYS appears on the horizontal axis of a scatter
plot? Answer: the explanatory variable
◉ words that describe direction Answer: positive/negative
◉ words that describe outliers/clusters Answer: points that are
outside most data
◉ words that describe form Answer: linear and non-linear
◉ words that describe strength Answer: very strong, moderately
strong, fairly weak
◉ What does the correlation measure? Answer: the strength of a
linear relationship
◉ TRUE OR FALSE : Two variables must both be quantitative in
order to find the correlation between them. Answer: True
, ◉ R value :1 Answer: positive correlation and perfect association
◉ Is correlation resistant to extreme observations? Explain. Answer:
No. (affect correlation significantly)
◉ What is the general form of a regression equation? Define each
variable in the equation. Answer: y(hat) = a + bx, y(hat) = predicted
y value, b = predicted slope and a = predicted y-intercept
◉ What is the difference between y and y hat? Answer: y = actual
responsive value
y hat = predicted responsive value
◉ What is extrapolation and why is this dangerous? Answer: making
predictions for explanatory outside range of observed and can be
very inaccurate
◉ R value : 0.45 Answer: positive, fairly weak association
◉ If a least squares regression line fits the data well, what
characteristic should the residual plot exhibit? Answer: no leftover
pattern
DEPENDENCE REVIEW SHEET 2026 FULL
EXPLANATION PROVIDED
◉ Which variable ALWAYS appears on the horizontal axis of a scatter
plot? Answer: the explanatory variable
◉ words that describe direction Answer: positive/negative
◉ words that describe outliers/clusters Answer: points that are
outside most data
◉ words that describe form Answer: linear and non-linear
◉ words that describe strength Answer: very strong, moderately
strong, fairly weak
◉ What does the correlation measure? Answer: the strength of a
linear relationship
◉ TRUE OR FALSE : Two variables must both be quantitative in
order to find the correlation between them. Answer: True
, ◉ R value :1 Answer: positive correlation and perfect association
◉ Is correlation resistant to extreme observations? Explain. Answer:
No. (affect correlation significantly)
◉ What is the general form of a regression equation? Define each
variable in the equation. Answer: y(hat) = a + bx, y(hat) = predicted
y value, b = predicted slope and a = predicted y-intercept
◉ What is the difference between y and y hat? Answer: y = actual
responsive value
y hat = predicted responsive value
◉ What is extrapolation and why is this dangerous? Answer: making
predictions for explanatory outside range of observed and can be
very inaccurate
◉ R value : 0.45 Answer: positive, fairly weak association
◉ If a least squares regression line fits the data well, what
characteristic should the residual plot exhibit? Answer: no leftover
pattern
