Question

X	Y/1	Y/0
Years Exp	Successful	Unsccessful	total
4	17	83	100
8	40	60	100
12	50	50	100
16	56	44	100
20	96	4	100

The data in tab #2 pertain to the years of experience of project managers and the numbers of successes and failures they have had on major projects. Use the data set given in tab #2 in the attached Excel workbook and logistic regression to find the following:

The probability of success given 10 years of experience is: .

The probability of failure given 18 years of experience is: .  

Answer 1

x	p	log (p/(1-p))
4	0.17	-1.585627264
8	0.4	-0.405465108
12	0.5	0
16	0.56	0.241162057
20	0.96	3.17805383

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.912588605
R Square	0.832817963
Adjusted R Square	0.777090617
Standard Error	0.832243508
Observations	5
ANOVA
	df	SS	MS	F	Significance F
Regression	1	10.35101	10.35100594	14.94451	0.030613
Residual	3	2.077888	0.692629256
Total	4	12.42889
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%	Lower 95.0%	Upper 95.0%
Intercept	-2.766572103	0.872864	-3.169532686	0.050499	-5.54442	0.011272	-5.54442	0.011272
x	0.254349734	0.065795	3.865813184	0.030613	0.044962	0.463738	0.044962	0.463738

ln(p/(1-p)) = -2.7665 + 0.2544 * x

x	ln(p/(1-p)	p
10	-0.223074765	0.444461
18	1.811723106	0.85957

The probability of success given 10 years of experience is: .

= 0.4445

The probability of failure given 18 years of experience is: .

= 1-0.85957

= 0.14043