Survey

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Regression analysis wikipedia, lookup

Linear regression wikipedia, lookup

Choice modelling wikipedia, lookup

Regression toward the mean wikipedia, lookup

Confidence interval wikipedia, lookup

Transcript
```Stat 401 Lab 4
Group Activity on Regression
Names of Group Members: _______________, _______________, _______________
_______________, _______________, _______________
How long does a bar of soap last? The data consists of the weight (grams) of a bar of
soap and the number of days since the bar was first used.
Days in use
Weight (g)
1
4
121 103
7
84
9
71
12
50
17
27
20
13
14
.
We wish to be able to predict the weight of the bar given the number of days since the bar
was first used. Use JMP to analyze these data. Use the JMP output that you generate and
members should discuss the questions and come up with answers that are agreed upon by
all the group members. Turn in this group answer sheet and one copy of your JMP output
at the end of lab today.
1. Give the prediction equation for the line relating days in use to weight.
2. Give an interpretation, within the context of the problem, of:
a. the estimated slope, β̂ 1 .
b. the estimated Y-intercept, β̂ 0 .
3. Is there a significant linear relationship between the days in use and the weight of
1
4. Give the value of R2 and an interpretation of this value.
5. The labeled weight of a new bar of soap is 4.25 oz (120.5 g). Based on your
prediction equation, is 120.5 g a plausible value for the mean weight of a new bar