# NMIMS – Decision Science

**Decision Science**

**1. **Consider the following data on the categories of YouTube Shorts and their views. The table shows the number of YouTube Shorts in each category that have been classified as either “High Views” (more than 1,000,000 views) or “Low Views” (1,000,000 views or less).

Category | High Views | Low Views |

Music | 50 | 100 |

Comedy | 30 | 170 |

Education | 20 | 180 |

Gaming | 40 | 160 |

Travel | 10 | 190 |

- What is the probability that a randomly selected YouTube Short is in the Music category?
- ii. What is the probability that a randomly selected YouTube Short has High Views?
- iii. What is the probability that a randomly selected YouTube Short has Low Views?
- iv. If a YouTube Short is known to be in the Comedy category, what is the probability that it has High Views?
- v. If a YouTube Short is known to have High Views, what is the probability that it is in the Gaming category?
**(10 Marks)**

**2. Use 4 month moving average, and 5 month moving average too.**

For which moving average Mean Square Error is less? **(10 Marks)**

Month | Total views on YouTube channel |

Jan-23 | 10484 |

Feb-23 | 10884 |

Mar-23 | 13372 |

Apr-23 | 14742 |

May-23 | 16141 |

Jun-23 | 17210 |

Jul-23 | 17303 |

Aug-23 | 18132 |

Sep-23 | 18208 |

Oct-23 | 19099 |

Nov-23 | 20936 |

Dec-23 | 21914 |

Jan-24 | 22892 |

Feb-24 | 23870 |

Mar-24 | 24848 |

Apr-24 | 25826 |

May-24 | 26803 |

Jun-24 | 27781 |

**3. a) **Use an appropriate chart to show the contribution of each category of sales with conclusion. Rahul has this channel and offers a variety of content to users. **(5 Marks)**

category | Average Views |

Music | 1,200,000 |

Comedy | 800,000 |

Education | 600,000 |

Gaming | 900,000 |

Travel | 700,000 |

**3. b) **Suppose we have the duration (in seconds) of 10 YouTube Shorts videos: 120, 130, 140, 125, 135, 150, 128, 132, 142, and 155. Calculate the mean (average) duration of these videos. (5 Marks)