In: Math
This is a written, statistical report, not simply a collection of different types of Excel output. It is not necessary to include the formulas you used or a copy of the dataset. When answering the questions, make sure to include any relevant statistics and/or the results of your calculations. Like any other written report, you will want to start with an introductory paragraph or problem statement and finish with a conclusion that summarizes the information presented.
1. Use descriptive statistics to summarize the data.
2. Develop a 95% confidence interval estimate of the mean age of unemployed individuals in Philadelphia.
3. Conduct a hypothesis test to determine whether the mean duration of unemployment in Philadelphia is greater than the national mean duration of 14.6 weeks. Use a .01 level of significance. What is your conclusion?
4. Is there a relationship between the age of an unemployed individual and the number of weeks of unemployment? Explain.
Age |
Weeks |
56 |
22 |
35 |
19 |
22 |
7 |
57 |
37 |
40 |
18 |
22 |
11 |
48 |
6 |
48 |
22 |
25 |
5 |
40 |
20 |
25 |
12 |
25 |
1 |
59 |
33 |
49 |
26 |
33 |
13 |
56 |
15 |
20 |
17 |
31 |
11 |
27 |
17 |
23 |
3 |
45 |
17 |
29 |
14 |
31 |
4 |
59 |
39 |
39 |
7 |
35 |
12 |
44 |
38 |
27 |
14 |
24 |
6 |
27 |
7 |
45 |
25 |
42 |
33 |
45 |
16 |
44 |
12 |
21 |
13 |
31 |
16 |
42 |
4 |
23 |
14 |
51 |
31 |
27 |
7 |
30 |
10 |
33 |
23 |
32 |
8 |
22 |
7 |
51 |
12 |
50 |
16 |
21 |
9 |
38 |
5 |
26 |
8 |
55 |
35 |
a)
Age | Weeks | ||
Mean | 36.6 | Mean | 15.54 |
Standard Error | 1.6893 | Standard Error | 1.4038 |
Median | 34 | Median | 13.5 |
Mode | 27 | Mode | 7 |
Standard Deviation | 11.9455 | Standard Deviation | 9.9267 |
Sample Variance | 142.6939 | Sample Variance | 98.5392 |
Kurtosis | -1.1451 | Kurtosis | 0.0537 |
Skewness | 0.3573 | Skewness | 0.9108 |
Range | 39 | Range | 38 |
Minimum | 20 | Minimum | 1 |
Maximum | 59 | Maximum | 39 |
Sum | 1830 | Sum | 777 |
Count | 50 | Count | 50 |
b)
Level of Significance , α =
0.05
degree of freedom= DF=n-1= 49
't value=' tα/2= 2.010 [Excel
formula =t.inv(α/2,df) ]
Standard Error , SE = s/√n = 11.9455 /
√ 50 = 1.6893
margin of error , E=t*SE = 2.0096
* 1.6893 = 3.3949
confidence interval is
Interval Lower Limit = x̅ - E = 36.60
- 3.394861 = 33.2051
Interval Upper Limit = x̅ + E = 36.60
- 3.394861 = 39.9949
95% confidence interval is (
33.21 < µ < 39.99
)
c)
Ho : µ = 14.6
Ha : µ > 14.6
(Right tail test)
Level of Significance , α =
0.01
sample std dev , s = √(Σ(X- x̅ )²/(n-1) )
= 9.9267
Sample Size , n = 50
Sample Mean, x̅ = ΣX/n =
15.5400
degree of freedom= DF=n-1= 49
Standard Error , SE = s/√n = 9.9267 / √
50 = 1.4038
t-test statistic= (x̅ - µ )/SE = ( 15.540
- 14.6 ) / 1.4038
= 0.670
critical t value, t* =
2.4049 [Excel formula =t.inv(α/no. of tails,df)
]
p-Value = 0.2531 [Excel formula
=t.dist(t-stat,df) ]
Decision: p-value>α, Do not reject null hypothesis
Conclusion: There is not enough evidence to conclude that the mean
duration of unemployment in Philadelphia is greater than the
national mean duration of 14.6 weeks
d)
correlation coefficient between two variables=0.6591
so, there is moderate positive linear relationship between the age of an unemployed individual and the number of weeks of unemployment