Question

5) A project manager at System Design Corporation has collected the following data on the size of software programs and the length of programming time. The company is bidding on a new system that is estimated to consist of 300,000 lines of code. Use a scatter plot to find the correlation function of coding time to the program size and estimate the number of days it would take to code the system.

Module Size in 1000 lines of code Number of days to code

(KLOC)

1	150	72
2	158	66
3	148	65
4	120	60
5	178	75
6	170	68
7	152	68
8	138	65
9	200	80
10	195	75
11	189	65
12	173	68
13	159	62
14	163	71
15	150	65
16	140	65
17	206	74
18	144	64
19	157	70
20	183	76
21	195	75
22	190	77
23	185	73
24	152	58
25	178	70

Answer 1

solution:

using should be Pearson's Corelation coefficient, r

Module	Size in 1000 lines of code (KLOC), x	Number of days to code, y	X^2	Y^2	XY
1	150	72	22500	5184	(150*72)=10800
2	158	66	24964	4356	(158*66)=10428
3	148	65	21904	4225	(148*65)=9620
4	120	60	14400	3600	(120*60)=7200
5	178	75	31684	5625	(178*75)=13350
6	170	68	28900	4624	(170*68)=11560
7	152	68	23104	4624	(152*68)=10336
8	138	65	19044	4225	(138*65)=8970
9	200	80	40000	6400	(200*80)=16000
10	195	75	38025	5625	(195*75)=14625
11	189	65	35721	4225	(189*65)=12285
12	173	68	29929	4624	(173*68)=11764
13	159	62	25281	3844	(159*62)=9858
14	163	71	26569	5041	(163*71)=11573
15	150	65	22500	4225	(150*65)=9750
16	140	65	19600	4225	(140*65)=9100
17	206	74	42436	5476	(206*74)=15244
18	144	64	20736	4096	(144*64)=9216
19	157	70	24649	4900	(157*70)=10990
20	183	76	33489	5776	(183*76)=13908
21	195	75	38025	5625	(195*95)=14625
22	190	77	36100	5929	(190*77)=14630
23	185	73	34225	5329	(185*73)=13505
24	152	58	23104	3364	(152*58)=8816
25	178	70	31684	4900	(178*70)=12460
Sum	4173	1727	708573	120067	290613

m = 0.1949227