SE250:lab-5:twon069

Task 1

• Ok, so this is a tough lab indeed, had quite a lot of problem because realizing the code doesn't work on Visual Studio so had to have cygwin set up on my computer at home to finish this lab. (took quite a while because I'm a total newbie at these shell stuff, however bvic helped a lot on the forum, so thanks!)

• During the lab, it took quite a while to figure out what the output meant and understanding the codes, luckily HTTB from last year was great and had explanation to each of the output, so that got my started.

Determining the Sample Size

• Ran a range of sample size to determine when the randomness start to not varie a lot

Results are:

SS = 10		3.584963	55%	50%	126.0833   36.34%	-0.341362
SS = 100	6.328758	20%	50%	131.7      4.51%	-0.135626
SS = 1000	7.843786         1%     95%     128.0860   0.29%        -0.017268
SS = 10000	7.985498         0%     99%     125.8253   1.26%        -0.000047
SS = 100000	7.998297         0%     75%     127.5775   0.71%         0.000327
SS = 1000000	7.999876         0%  99.99%     127.5198   0.19%        -0.000567

• The randomness starts to not vary as much starting from 10000, so SS I choose will be 100000

Results

buzhash low		7.99829	75.00%	127.577	0.71%	 0.000327
buzhashn low		7.99823	50.00%	127.493	0.13%	-0.003092
hash_CRC low		5.59830	0.01%	81.7834	24.53%	 0.028545
base256 low		0.00000	0.01%	97.000	27.32%	undefined
Java_Integer low	4.82824	0.01%	43.8834	27.32%	-0.092002
Java_Object low		2.00000	0.01%	77.000	27.32%	-0.521556
Java_String low		7.99958	99.99%	127.438	0.22%	-0.000646
rand low		7.95308	0.01%	111.441	11.17%	-0.051837
high rand low		7.99820	50.00%	127.402	0.59%	-0.001222

buzhash high		7.99823	2.50%	127.374	0.77%	-0.000076
buzhashn high		7.82387	50.00%	127.493	0.13%	-0.003092
hash_CRC high		7.84045	0.01%	122.862	1.98%	 0.018518
base256 high		4.02297	0.01%	107.853	27.32%	 0.034082
Java_Integer high	4.82824	0.01%	43.8834	27.32%	-0.092002
Java_Object high	5.70432	0.01%	89.7964	21.50%	-0.148185
Java_String high	7.94554	0.01%	126.139	0.27%	 0.021181
rand high		7.95315	0.01%	111.468	11.13%	-0.048905
high rand high		7.99807	50.00%	127.405	0.07%	-0.002226

Conclusion

• It was rather difficult putting up the results in a table, took a long time fiddling through each output.
• Just upon looking at the result of high entropy and low entropy, not a whole lot difference to the randomness of placement, pretty much the same, so it doesn't really matter if the collection of items has a high entropy or not.
• Its very hard to determine a ranking system between each hash function, however it can be clearly shown that buzhash, buzhashn and high random all generate a good randomness in their tables.
• Random does not fall into the above category even though it's Entropy is very close to 8 is due to it's Monte Carlo score, having a high percentage of error.
• Java_String too, did not make it in the above category, due to the low Chi Square mark, even though the overall mark was good.
• base256 is probably the worst out of all, having really low randomness mark in all areas.

Task 2

10/100:

Buzhash low 10/100: llps = 2, expecting 1.39006
Hash CRC low 10/100: llps = 1, expecting 1.39006
Base256 low 10/100: llps = 10, expecting 1.39006
Java Object low 10/100: llps = 10, expecting 1.39006
Java String low 10/100: llps = 1, expecting 1.39006

Buzhash high 10/100: llps = 2, expecting 1.39006
Hash CRC high CRC 10/100: llps = 1, expecting 1.39006
Base256 high 10/100: llps = 2, expecting 1.39006
Java Object high 10/100: llps = 1, expecting 1.39006
Java String high 10/100: llps = 1, expecting 1.39006

Buzhashn 10/100: llps = 1, expecting 1.39006
Java Integer 10/100: llps = 1, expecting 1.39006

100/100:

Buzhash low 100/100: llps = 3, expecting 4.22683
Hash CRC low 100/100: llps = 6, expecting 4.22683
Base256 low 100/100: llps = 100, expecting 4.22683
Java Object low 100/100: llps = 100, expecting 4.22683
Java String low 100/100: llps = 3, expecting 4.22683

Buzhash high 100/100: llps = 3, expecting 4.22683
Hash CRC high CRC 100/100: llps = 4, expecting 4.22683
Base256 high 100/100: llps = 4, expecting 4.22683
Java Object high 100/100: llps = 5, expecting 4.22683
Java String high 100/100: llps = 3, expecting 4.22683

Buzhashn 100/100: llps = 4, expecting 4.22683
Java Integer 100/100: llps = 1, expecting 4.22683

1000/100:

Buzhash low 1000/100: llps = 22, expecting 18.7606
Hash CRC low 1000/100: llps = 43, expecting 18.7606
Base256 low 1000/100: llps = 1000, expecting 18.7606
Java Object low 1000/100: llps = 1000, expecting 18.7606
Java String low 1000/100: llps = 15, expecting 18.7606

Buzhash high 1000/100: llps = 22, expecting 18.7606
Hash CRC high CRC 1000/100: llps = 25, expecting 18.7606
Base256 high 1000/100: llps = 103, expecting 18.7606
Java Object high 1000/100: llps = 47, expecting 18.7606
Java String high 1000/100: llps = 19, expecting 18.7606

Buzhashn 1000/100: llps = 16, expecting 18.7606
Java Integer 1000/100: llps = 10, expecting 18.7606

10000/100:

Buzhash low 10000/100: llps = 125, expecting 125.959
Hash CRC low 10000/100: llps = 409, expecting 125.959
Base256 low 10000/100: llps = 10000, expecting 125.959
Java Object low 10000/100: llps = 10000, expecting 125.959
Java String low 10000/100: llps = 110, expecting 125.959

Buzhash high 10000/100: llps = 127, expecting 125.959
Hash CRC high CRC 10000/100: llps = 146, expecting 125.959
Base256 high 10000/100: llps = 671, expecting 125.959
Java Object high 10000/100: llps = 425, expecting 125.959
Java String high 10000/100: llps = 123, expecting 125.959

Buzhashn 10000/100: llps = 128, expecting 125.959
Java Integer 10000/100: llps = 100, expecting 125.959

• Java_Object, Base256, Hash CRC performed poorly.
• Buzhash and Buzhashn stays with the expected values.