17C

Variable name Definition
competitorname The name of the Halloween candy
chocolate Does it contain chocolate?
fruity Is it fruit flavored?
caramel Is there caramel in the candy?
peanutyalmondy Does it contain peanuts, peanut butter, or almonds?
nougat Does it contain nougat?
crispedricewafer Does it contain crisped rice, wafers, or a cookie component?
hard Is it a hard candy?
bar Is it a candy bar?
pluribus Is it one of many candies in a bag or box?
sugarpercent The percentile of sugar it falls under within the dataset.
pricepercent The unit price percentile compared to the rest of the set.
winpercent The overall win percentage according to 269,000 matchups.
Parameter Estimate Standard
error		 t-value Pr > |t|
Intercept 42.93 2.88 14.91 <.0001
peanutyalmondy = TRUE 15.34 3.90 3.93 0.0002
sugarpercent 10.14 5.15 1.97 0.0523
Parameter Estimate Standard
error		 t-value Pr > |t|
Intercept 43.40 3.01 14.41 <.0001
peanutyalmondy = TRUE 10.48 9.63 1.09 0.2799
sugarpercent 9.15 5.48 1.67 0.0985
sugarpercentpeanutyalmondy = TRUE 9.23 16.69 0.55 0.5818
peanutyalmondy indicator variable value Estimated model equation
peanutyalmondy  1 or TRUE  _________  ________
peanutyalmondy  0 or FALSE  _________ ________
LeadLevels Elevation_Feet Direction
3.475 2000 west
3.359 2000 west
3.877 2000 west
4 2500 west
3.618 2500 west
2.644 2500 west
4.575 3000 west
8.6 3000 west
6.952 3000 east
4.349 3000 east
Parameter Estimate Standard
Error		 t-value Pr > |t|
Intercept 2.385 5.393 0.44 0.6598
Direction = east 3.201 7.670 0.42 0.6777
Elevation_Feet 0.002 0.002 0.84 0.4014
Elevation_Feet * Direction = east -0.001 0.003 -0.44 0.6629
Variable Description
ID Identification number
Height Height in centimeters (cm)
Weight Weight in kilograms (kg)
Age Age in years
Sex Male/female
Smokes Are you a regular smoker? (yes/no)
Alcohol Are you a regular drinker? (yes/no)
Exercise What is your frequency of exercise? (low, moderate, high)
GroupAssignment Whether the student ran or sat between the first and second pulse measurements
Pulse1 First pulse measurement (rate per minute)
Pulse2 Second pulse measurement (rate per minute)
Year Year of class (1993–1998)
Skill or Concept: I can . . . Questions to check your understanding Rating
from 1 to 5
Interpret the trend of a linear regression model with two explanatory variables. 5, 6, 8
Visualize an interaction between a continuous explanatory variable and a categorical explanatory variable using a scatterplot. 1–4

7, 9

An assortment of sweets. A scatterplot labeled “sugar percent” on the horizontal axis and “winpercent” on the y-axis. There is a legend titled peanutyalmondy showing that the blue line and points indicate TRUE and the red line and points indicate FALSE. The red dots are very spread out but arranged in a loosely linear pattern. The red line has a positive slope. The blue dots are also spread out in a loosely linear pattern and the blue line appears to have a similar slope to the red line, but is above it. A scatterplot labeled “sugar percent” on the horizontal axis and “winpercent” on the y-axis. There is a legend titled peanutyalmondy showing that the blue line and points indicate TRUE and the red line and points indicate FALSE. The red dots are very spread out but arranged in a loosely linear pattern. The red line has a positive slope. The blue dots are also spread out in a loosely linear pattern and the blue line has a steeper positive slope than the red line. It is also higher than the red line.

Glossary

interaction
when an explanatory variable has a different effect on the response variable.
interaction term
a variable that represents an interaction between two variables.