辅导parametric analysis、讲解Java/c++程序语言、辅导Python，c++编程设计
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Question 12
The data below are the final weights of chicks (in grams) at six weeks, after having been fed on one of six diets. The trial was designed to study the comparative feeding values of six protein supplements. Ten chicks were used per lot. The birds were all of the same sex and age and from the same flock. All rations had the same level of crude protein. (Casein is a milk protein and forms the basis of cheese.)
All birds receiving each ration were housed together. Record was kept of the amount of feed eaten by lots only.
Analyse the data as fully as possible. (This means plot the data, try an appropriate parametric analysis, check the assumptions, use non-parametric analysis if necessary.) As- suming that a parametric analysis is valid, examine significant treatment differences using both appropriate contrasts and one, or more, multiple comparison techniques. Compare these two approaches. Note that the descriptions in brackets may aid in determining mean- ingful contrasts.
Comment on the results of the experiment, including a discussion of some of the disad- vantages of the experimental design and how you might improve it.
Source of protein supplement
Horsebean
(Vegetable) Linseed oil meal
(Vegetable) Soybean oil meal
(Vegetable) Sunflower seed oil meal (Vegetable) Meat meal
(Animal) Casein
(Animal)
(Bean) (Oil) (Oil) (Oil) (Meat) (Dairy)
179 309 243 423 325 368
160 229 230 340 257 390
136 181 248 392 303 379
227 141 327 339 315 260
217 260 329 341 380 404
168 203 250 226 153 318
108 148 193 320 263 352
124 169 271 295 242 359
143 213 316 334 206 216
140 257 267 322 344 222
Question 13
An experiment was run to compare the effects of auditory and visual cues on the speed of response of a human subject. A stimulus was presented to each subject on a computer and the reaction time required for the subject to press a key was recorded. The cue was either auditory or visual was presented 5, 10, or 15 seconds before the stimulus, with the corresponding reaction time recorded below.
Treatment 1 2 3 4 5 6
Cue Auditory Auditory Auditory Visual Visual Visual
Lag (sec) 5 10 15 5 10 15
0.204 0.167 0.202 0.257 0.283 0.256
0.170 0.182 0.198 0.279 0.235 0.281
0.181 0.187 0.236 0.269 0.260 0.258
a) Identify a set of contrasts that would be interesting (and appropriate) in this experi- ment.
b)Plot the data and comment on any differences that you see.
c)Perform a hypothesis test to determine whether there are significant differences be- tween the six different treatments.
d)Test the significance of the contrasts that you identified in a).
e)Draw the appropriate residual plots and comment on the appropriateness of this model.
Question 14
Consider the linear model for the completely randomised design with a = 5 and n = 10. Derive the normal equations for this model and use the normal equations to find estimates for μ and τi for i = 1, · · · , 5. Use actual values of a and n as soon as possible.
Question 12
The data below are the final weights of chicks (in grams) at six weeks, after having been fed on one of six diets. The trial was designed to study the comparative feeding values of six protein supplements. Ten chicks were used per lot. The birds were all of the same sex and age and from the same flock. All rations had the same level of crude protein. (Casein is a milk protein and forms the basis of cheese.)
All birds receiving each ration were housed together. Record was kept of the amount of feed eaten by lots only.
Analyse the data as fully as possible. (This means plot the data, try an appropriate parametric analysis, check the assumptions, use non-parametric analysis if necessary.) As- suming that a parametric analysis is valid, examine significant treatment differences using both appropriate contrasts and one, or more, multiple comparison techniques. Compare these two approaches. Note that the descriptions in brackets may aid in determining mean- ingful contrasts.
Comment on the results of the experiment, including a discussion of some of the disad- vantages of the experimental design and how you might improve it.
Source of protein supplement
Horsebean
(Vegetable) Linseed oil meal
(Vegetable) Soybean oil meal
(Vegetable) Sunflower seed oil meal (Vegetable) Meat meal
(Animal) Casein
(Animal)
(Bean) (Oil) (Oil) (Oil) (Meat) (Dairy)
179 309 243 423 325 368
160 229 230 340 257 390
136 181 248 392 303 379
227 141 327 339 315 260
217 260 329 341 380 404
168 203 250 226 153 318
108 148 193 320 263 352
124 169 271 295 242 359
143 213 316 334 206 216
140 257 267 322 344 222
Question 13
An experiment was run to compare the effects of auditory and visual cues on the speed of response of a human subject. A stimulus was presented to each subject on a computer and the reaction time required for the subject to press a key was recorded. The cue was either auditory or visual was presented 5, 10, or 15 seconds before the stimulus, with the corresponding reaction time recorded below.
Treatment 1 2 3 4 5 6
Cue Auditory Auditory Auditory Visual Visual Visual
Lag (sec) 5 10 15 5 10 15
0.204 0.167 0.202 0.257 0.283 0.256
0.170 0.182 0.198 0.279 0.235 0.281
0.181 0.187 0.236 0.269 0.260 0.258
a) Identify a set of contrasts that would be interesting (and appropriate) in this experi- ment.
b)Plot the data and comment on any differences that you see.
c)Perform a hypothesis test to determine whether there are significant differences be- tween the six different treatments.
d)Test the significance of the contrasts that you identified in a).
e)Draw the appropriate residual plots and comment on the appropriateness of this model.
Question 14
Consider the linear model for the completely randomised design with a = 5 and n = 10. Derive the normal equations for this model and use the normal equations to find estimates for μ and τi for i = 1, · · · , 5. Use actual values of a and n as soon as possible.