Outliers and the LSRL

Identify any outliers.

• Outlier at x = 18

• Outlier at x = 12

• Outlier at x = 6

• There aren't any outliers in this graph.

Tags

CCSS.8.SP.A.1

Identify any outliers.

• Outlier at x = 10

• Outlier at x = 15

• Outlier at x = 30

• There aren't any outliers in this graph.

Tags

CCSS.8.SP.A.1

If the point with the red x is removed from the scatterplot, what will happen to the slope of the LSRL and the correlation coefficient?

• slope increases, r increases

• slope decreases, r increases

• slope increases, r decreases

• slope decreases, r decreases

• slope is unchanged, r increases

If another data point were added with an air temperature of 0 Celcius and a stopping distance of 80 feet, the correlation would

• decrease, since this new point is an outlier that does not follow the pattern in the data

• increase, since this new point is an outlier that does not follow the pattern in the data

• stay nearly the same, since correlation is resistant to outliers

• increase, since there would be more data points.

• Whether this data point causes an increase or decrease cannot be determined without recalculating the correlation

The point in the upper right hand corner of the scatterplot is

• not an outlier or an influential point
• not an outlier but an influential point
• an outlier and an influential point
• an outlier but not an influential point

Tags

CCSS.8.SP.A.1

Mr. Nerdly asked the students in his AP Statistics class to report their overall grade point averages and their SAT Math scores. The scatterplot below provides information about his students’ data. The dark line is the least-squares regression line for the data, and its equation is

ŷ = 410.54 + 67.3x

Which of the following statements about the circled point is true? (click on the picture to enlarge)

• The standard score for this student’s GPA is positive.

• If we used the least-squares line to predict this student’s SAT Math score, we would make a prediction that is too low.

• This student’s residual is positive.

• Removing this data point would not change the correlation between SAT math score and GPA.

• Removing this student’s data point would decrease the slope of the least-squares line

Tags

CCSS.HSS.ID.B.6B

An influential observation is most often

• larger than most other values in the y–direction
• larger than most other values in the x–direction
• not an outlier
• an outlier in the x direction

An influential point in the context of least square regression lines is a

• point far from all the other points
• point that, when omitted, causes the line to change significantly
• point that all other points are centered around
• None of these

What is true about the point B?

• influences slope: Influences correlation

• Does NOT influence slope: Does NOT influence correlation

• Influences slope: Does NOT influence correlation

• Does NOT influence slope: Influences correlation

Tags

CCSS.8.SP.A.1

All outliers influence the slope's value.

• True

• False