1. Which of the following measures the spread of data?

1. Mean
2. Median and interquartile range
3. First and third quartiles
4. Standard deviation and variance

Answer: (4) Standard deviation and variance

2. The middle value in a set of observed values is:

1. Mode
2. Range
3. Median
4. Mean

Explanation:
-> Mode represents the value that appears most frequently in a data set.
-> Range is the difference between the highest and lowest values in a group interval.
-> Mean is the average or the most value in a collection of numbers.

3. The simplest measurement of central tendency is:

1. Mean
2. Median
3. Mode
4. Standard deviation

Explanation:
-> Mode represents the value that appears most frequently in a data set.
-> Range is the difference between the highest and lowest values in a group intervals.
-> Mean is the average or the most value in a collection of numbers.

4. To identify the shape of univariate data, what type of graph would be the most useful?

1. Histogram
2. Scatter plot
3. Bar chart
4. Pie chart

Explanation:
-> Bar graph: shows the number in categories
-> Scatter plot: to determine whether or not two variables have a relationship or correlation.
-> Pie chart: compare parts of the data to the whole

5. Sample surveys are types of

1. Secondary data
2. Tertiary data
3. Manipulated data
4. Primary data

Explanation:
-> Primary data: data collected by researchers directly from main sources. Eg: interviews, surveys, experiments, etc.
-> Secondary data: data that is collected by someone other than the primary user. Eg: censuses, information collected by government departments, organizational records, etc.
-> Tertiary data: based on a collection of primary and secondary sources. Eg: textbooks, manuals, encyclopedias, etc.

6. The degree of freedom can be calculated using the formula

1. (n-2)
2. (n+1)
3. (n-1/2)
4. (n-1)