Statistics II
This course contains basics of statistics, descriptive statistics, probability, sampling, random variables and mathematical expectations, probability distribution, correlation and regression
Tribhuvan University
Institute of Science and Technology
Model Set Ii
Bachelor Level / third-semester / Science
Computer Science and Information Technology( STA215 )
Statistics II
Full Marks: 60 + 20 + 20
Pass Marks: 24 + 8 + 8
Time: 3 Hours
Candidates are required to give their answers in their own words as far as practicable.
The figures in the margin indicate full marks.
Group A
Attempts any TWO questions
A study was conducted to IT students to complete a certain maze. The following data revels the time taken in seconds to complete the maze by eight students each BCA and Bcs. CSIT
| BCA | 8 | 12 | 13 | 9 | 3 | 8 | 14 | 11 |
| CSIT | 10 | 15 | 10 | 11 | 4 | 7 | 12 | 10 |
Can it can be concluded that the Bsc students are more efficient than BCA student. Use 5% level of significant.
The table shows the corresponding vales of the three variables Y, X1 and X2
| Y | 6 | 11 | 10 | 7 | 5 | 12 |
| X1 | 1 | 3 | 2 | -2 | 3 | 6 |
| X2 | 3 | -1 | 2 | 4 | 7 | 3 |
Estimate the Y when X1 = -9 and X2 = 4
The table given below are the yields of 4 varieties in a 4 replicate experiment in which one observation is missing. Analyze the data after finding missing value
| A 12 | C 19 | B 10 | D 10 |
| C 17 | B 13 | D 7 | A ? |
| B 21 | D 11 | A 6 | C 19 |
| D 12 | A 7 | C 27 | B 18 |
Group B
Attempts any EIGHT questions
In random sample of 200 chips from a large consignment, 29 items were found to be defective, find the 95% confidence limits for the percentage of defective chips in the consignments.
A manufacture claim that their widget is more reliable than their main competitors. In order to verify this a sample of 65 widget from manufacturer’s range was taken. This mean rate found to be 992 per 1000 with sd 15 per 1000. previous studies have shown that the mean pass rate of all weight on the market is 979 per 1000. Test the manufacturer’s claim at 5% level of significance.
What are parametric and non-parametric test? Write some advantage and disadvantage of non-parametric test.
Life in years of two types of electronic motors used in irrigation of farms are given below
| M1 | 3 | 6 | 7 | 4 | 3 | 5 | 5 | 4 | 3 |
| M2 | 4 | 3 | 5 | 6 | 3 | 2 | 4 | 7 | 6 |
Is there any significant different between two types of motors? Use Kolmogorov Smirnov test at 5% level of significance.
Five laptop users were asked for the acceptability of four brands for daily use. The responses of acceptability (A) and rejection (R) are given below
| Users | Brands | |||
| Alpha | Beta | Delta | Gamma | |
| H1 | A | R | A | R |
| H2 | R | A | A | R |
| H3 | R | A | R | A |
| H4 | A | R | R | R |
| H5 | A | A | R | A |
Test whether is any significance difference between brands with respect to acceptability, Use (Cochran Q test)
For the following data consists r12 = 0.8, r23 = 0.9 and r13 = 0.82 find the r23.1 and R1.23 interpreted the results.
What is Binomial and Poisson process?
In computer network of a software company arrival of printing message follows poission law on an average at every 10 minutes, printer prints message takes on an average 6 minutes to print following exponential law. Find
- average arrival rate and average service rate for 1 hour
- average arrival rate and average rate for 15 min
Complete the following table
| SV | Df | SS | MSS | F |
| Blocks | 5 | 27 | ? | ? |
| Treatment | 4 | ? | ? | ? |
| Error | ? | ? | 4 | |
| Total | ? | 88 |