Page 193 - Data Science class 10
P. 193
Unsolved Exercise
Objective Type Questions (Section A)
A. Tick ( ) the correct option.
1. What measures of position divides the distribution into 4 equal parts? [CBSE Handbook]
a. Quartiles b. Deciles
c. Percentiles d. Range
2. In ____________________ joins, none of the associated tables have primary key column.
a. One to one b. One to many
c. Many to many d. None of these
3. Which of the following is correct about z-score? [CBSE Handbook]
a. It is the number of standard deviations a particular score lies above or below the mean of the set of scores.
b. It is a standardised measure of the mean of a set of data.
c. It is the average frequency of scores in a sample.
d. It is a measure of central tendency in the data.
4. In which of the following conditions is the standard deviation on the mean?
a. When z-score > 0 b. When z-score < 0
c. When z-score = 0 d. All of these
5. A ____________________ has 100 categorical buckets.
a. percentile b. quartile
c. decile d. interquartile range
B. Fill in the blanks.
1. In ____________________ join, both tables must have primary key columns.
2. The ____________________ quartile is the 25th percentile.
3. A standard normal distribution is a normally shaped distribution with a mean of ____________________ and a standard
deviation of ____________________ .
4. The third quartile (Q3, or the upper quartile) is the ____________________ percentile.
5. A decile has ____________________ categorical buckets.
Standard Questions (Section B)
A. Short answer type questions:
1. Define one to many join.
2. Why is a z-score so important?
3. What is quartile?
4. What do you mean by second quartile?
5. What is decile?
Data Merging 191

