Task 1 Display the ids of all students who sent friend requests to those studying 2 grades lower. Task 2 In the social network, users have the following achievements: 1. "School Star" awarded to the student with the highest number of friends. 2. "Hachiko" awarded to the student who sent the most friend requests, but no one confirmed the friendship. Display the ids of students who received achievements and the name of their achievement.
There is a normal distribution with a mean of 5 and a variance of 9. What are the mode and median?
What is the null hypothesis and the alternative hypothesis?
/* Task 2 In a social network, users have access to the following achievements: 1. "Star of the School" is awarded to the student with the highest number of friends. 2. "Hachiko" is awarded to the student who sent the highest number of friend requests, but none of the students confirmed the friendship. Output the ids of the students who received the achievement, as well as the name of their achievement. */
# You need to write a function f that subtracts the second string from the first. # Subtraction occurs only when the second string is the beginning of the first, # otherwise the function returns the first string. # f('hello world', 'hello') -> ' world' # f('hello world', 'hola') -> 'hello world' # f('hello world hello!', 'hello') -> ' world hello!'
Case: Several analytics teams calculate retention, and each gets a different value. Why could this happen? What will you do? How will you check?
Tell about yourself and your experience.
What is a Type I error (alpha) and a Type II error (beta)?
What statistical criteria do you know? Which ones are used for which metrics?
