% SUMMARY:
% 
% Data from an experiment on the affects of machine adjustments on
% the time to count bolts.  Data appear as the STATS (Issue 10) Challenge.
% 
% DATA:
% 
% Submitted by W. Robert Stephenson, Iowa State University
%                             email: wrstephe@iastate.edu
% 
% A manufacturer of automotive accessories provides hardware, e.g. nuts,
% bolts, washers and screws, to fasten the accessory to the car or truck.
% Hardware is counted and packaged automatically.  Specifically, bolts
% are dumped into a large metal dish.  A plate that forms the bottom of
% the dish rotates counterclockwise.  This rotation forces bolts to the
% outside of the dish and up along a narrow ledge.  Due to the vibration
% of the dish caused by the spinning bottom plate, some bolts fall off 
% the ledge and back into the dish.  The ledge spirals up to a point 
% where the bolts are allowed to drop into a pan on a conveyor belt.  
% As a bolt drops, it passes by an electronic eye that counts it.  When 
% the electronic counter reaches the preset number of bolts, the
% rotation is stopped and the conveyor belt is moved forward.  
% 
% There are several adjustments on the machine that affect its operation.  
% These include; a speed setting that controls the speed of rotation
% (SPEED1) of the plate at the bottom of the dish, a total number of 
% bolts (TOTAL) to be counted, a second speed setting (SPEED2) that is 
% used to change the speed of rotation (usually slowing it down) for the
% last few bolts, the number of bolts to be counted at this second speed
% (NUMBER2), and the sensitivity of the electronic eye (SENS).  The 
% sensitivity setting is to insure that the correct number of bolts are 
% counted.  Too few bolts packaged causes customer complaints.  Too many
% bolts packaged increases costs.  For each run conducted in this 
% experiment the correct number of bolts was counted.  From an
% engineering standpoint if the correct number of bolts is counted, the 
% sensitivity should not affect the time to count bolts.  The measured 
% response is the time (TIME), in seconds, it takes to count the desired
% number of bolts.  In order to put times on a equal footing the
% response to be analyzed is the time to count 20 bolts (T20BOLT).
% Below are the data for 40 combinations of settings.  RUN is the order 
% in which the data were collected.
% 
% Analyze the data.  What adjustments have the greatest effect on the 
% time to count 20 bolts?  How would you adjust the machine to get
% the shortest time to count 20 bolts?  Are there any unusual features
% to the data?
% 
%                             Data
% 
% RUN   SPEED1   TOTAL   SPEED2   NUMBER2   SENS   TIME   T20BOLT
% 
% 
% The data description and data may be freely used for non-commercial
% purposes and can be freely distributed.  Copyright remains with the
% author and STATS Magazine.
%
%
% Information about the dataset
% CLASSTYPE: numeric
% CLASSINDEX: last
%

@relation bolts

@attribute RUN INTEGER
@attribute SPEED1 {2,4,6}
@attribute TOTAL {10,20,30}
@attribute SPEED2 REAL
@attribute NUMBER2 {0,1,2}
@attribute SENS {6,8,10}
@attribute TIME REAL
@attribute T20BOLT REAL

@data
25,2,10,1.5,0,6,5.70,11.40
24,2,10,1.5,0,10,17.56,35.12
30,2,10,1.5,2,6,11.28,22.56
2,2,10,1.5,2,10,8.39,16.78
40,2,10,2.5,0,6,16.67,33.34
37,2,10,2.5,0,10,12.04,24.08
16,2,10,2.5,2,6,9.22,18.44
22,2,10,2.5,2,10,3.94,7.88
33,2,30,1.5,0,6,27.02,18.01
17,2,30,1.5,0,10,19.46,12.97
28,2,30,1.5,2,6,18.54,12.36
27,2,30,1.5,2,10,25.70,17.13
14,2,30,2.5,0,6,19.02,12.68
13,2,30,2.5,0,10,22.39,14.93
4,2,30,2.5,2,6,23.85,15.90
21,2,30,2.5,2,10,30.12,20.08
23,6,10,1.5,0,6,13.42,26.84
35,6,10,1.5,0,10,34.26,68.52
19,6,10,1.5,2,6,39.74,79.48
34,6,10,1.5,2,10,10.60,21.20
31,6,10,2.5,0,6,28.89,57.78
9,6,10,2.5,0,10,35.61,71.22
38,6,10,2.5,2,6,17.20,34.40
15,6,10,2.5,2,10,6.00,12.00
39,6,30,1.5,0,6,129.45,86.30
8,6,30,1.5,0,10,107.38,71.59
26,6,30,1.5,2,6,111.66,74.44
11,6,30,1.5,2,10,109.10,72.73
6,6,30,2.5,0,6,100.43,66.95
20,6,30,2.5,0,10,109.28,72.85
10,6,30,2.5,2,6,106.46,70.97
32,6,30,2.5,2,10,134.01,89.34
1,4,20,2.0,1,8,10.78,10.78
3,4,20,2.0,1,8,9.39,9.39
5,4,20,2.0,1,8,9.84,9.84
7,4,20,2.0,1,8,13.94,13.94
12,4,20,2.0,1,8,12.33,12.33
18,4,20,2.0,1,8,7.32,7.32
29,4,20,2.0,1,8,7.91,7.91
36,4,20,2.0,1,8,15.58,15.58
