Business Statistics
1. The sample data from a research survey conducted in various cities on the amount of time 13-15 year-old children spent with mobiles are as follows:
| City | Time with mobiles
(hours per week) |
| Hyderabad | 46 |
| Mumbai | 50 |
| Pune | 46 |
| Bangalore | 54 |
| Bhubneshwar | 42 |
| Indore | 30 |
| Bhopal | 42 |
| New Delhi | 50 |
| Chandigarh | 46 |
For the above sample, determine the following measures:
i. The mean
ii. The standard deviation
iii. The mode
iv. The 75th percentile
Based on your calculations comment on the time spent on mobile.
2. ‘Mumbai Ice Cream an ice cream store gives relationship between ice cream sold and temperature. The store has taken a sample of a week’s data. Below you are given the results of the sample
| Day | Cones Sold | Temperature |
| 1 | 350 | 110 |
| 2 | 200 | 100 |
| 3 | 210 | 90 |
| 4 | 100 | 80 |
| 5 | 80 | 70 |
| 6 | 70 | 60 |
| 7 | 50 | 50 |
i. Which variable is the dependent variable?
ii. Compute the least squares estimated line.
iii. Is there a significant relationship between the sales of cones and temperature?
iv. Predict sales of a 95 degree day.
3. According to one of the recent study conducted by an academic researcher on international placement of students from leading institutes in India there is a high variation in the salary offered by institutes. The following details have been gathered from the placement institute of the colleges. The researcher wants to understand the trends with regard to international placement based on the data he has gathered.
| Amount (in USD in lakhs per annum ) | Age | Marital Status | Type of institute | Gender |
| 2 | 35 | Single | University | Male |
| 5 | 24 | Married | PGDM | Male |
| 3.5 | 29 | Married | University | Female |
| 5 | 26 | Single | University | Male |
| 4 | 26 | Married | PGDM | Female |
| 8 | 25 | Single | PGDM | Female |
| 15 | 34 | Married | PGDM | Male |
| 3 | 26 | Single | PGDM | Male |
| 7 | 23 | Single | PGDM | Male |
a. Using descriptive statistics explore salary, and identify factors that appear to influence the amount of the salary received.
b. Do a correlation analysis between ‘Amount’ and ‘Age’ and interpreted the coefficient of correlation.