一部分可以用列联表的卡方检验来检验纤维的种类（fiber）和膨胀感(float)是否独立。

另一部分用单因素分析消耗掉的热量对于每一种纤维的饼干是否显著来检测减肥效果。

不知道这样做对不对，以及还需要其他方法吗？谢谢。

Story Name: High Fiber Diet Plan

Story Topics: Health

Datafile Name: Fiber

Methods: Contingency table , Chi square test

Abstract: A manufacturer was considering marketing crackers high in a certain kind of edible fiber as a dieting aid. Dieters would consume some crackers before a meal, filling their stomachs so that they would feel less hungry and eat less. A laboratory studied whether people would in fact eat less in this way.

Overweight female subjects ate crackers with different types of fiber (bran fiber, gum fiber, both, and a control cracker) and were then allowed to eat as much as they wished from a prepared menu. The amount of food they consumed and their weight were monitored, along with any side effects they reported. Unfortunately, some subjects developed uncomfortable bloating and gastric upset from some of the fiber crackers. A contingency table of "Cracker" versus "Bloat" shows the relationship between the four different types of cracker and the four levels of severity of bloating as reported by the subjects.

A Chi-Square test can be used to test whether Bloating is independent of Cracker (the type of fiber eaten).

Image: The residuals from the Contingency Table help to find the cells where the violation of the null hypothesis is greatest.

Datafile Name: Fiber

Datafile Subjects: Health

Story Names: High Fiber Diet Plan

Reference: This data is distributed with the software package, Data Desk? Data Description, Inc. (1993). Data Desk? Ithaca, NY: Data Description, Inc.

Authorization:

Description: Effects of dietary fiber. 12 female subjects were fed a controlled diet. Before each meal they ate crackers containing either bran fiber, gum fiber, a combination of both, or no fiber (control). Their caloric intake was monitored. Subjects reported any gastric or other problems.

Number of cases: 12

Variable Names:

1. Cracker: Type of fiber in the cracker
2. Diet: One of four diets (type of cracker)
3. Subject: An identification for each of the 12 subjects
4. Digested: Digested calories. Difference between caloric intake and calories passed through system
5. Bloat: Degree of bloating and flatulence reported by the subjects

The Data:

Cracker Diet    Subject Digested       Bloat

control 1       3       1772.84 none

bran    4       3       1752.63 low

combo   3       9       2121.97 med

gum     2       4       2558.61 high

gum     2       1       2026.91 med

bran    4       1       2047.42 low

combo   3       1       2254.75 low

control 1       1       2353.21 med

combo   3       2       2153.36 none

gum     2       2       2331.19 none

bran    4       2       2547.77 none

control 1       2       2591.12 none

gum     2       3       2012.36 low

combo   3       3       1956.18 low

combo   3       4       2025.97 none

bran    4       4       1669.12 none

control 1       4       2452.73 none

bran    4       5       2207.37 low

gum     2       5       1944.48 med

control 1       5       1927.68 low

combo   3       5       2190.1  high

control 1       6       1635.28 none

combo   3       6       1693.35 low

bran    4       6       1707.34 low

gum     2       6       1871.95 high

gum     2       7       2245.03 none

combo   3       7       2436.79 low

control 1       7       2667.14 low

bran    4       7       2766.86 none

bran    4       8       2279.82 none

combo   3       8       1844.77 high

gum     2       8       2002.73 high

control 1       8       2220.22 med

control 1       9       1888.29 low

gum     2       9       1804.27 high

bran    4       9       2293.27 med

bran    4       10      2357.4  none

control 1       10      2359.9  none

combo   3       10      2292.46 low

gum     2       10      2433.46 high

gum     2       11      1681.86 low

control 1       11      1902.75 none

bran    4       11      2003.16 none

combo   3       11      2137.12 med

combo   3       12      2203.07 med

control 1       12      2125.39 low

gum     2       12      2166.77 med

bran    4       12      2287.52 none