PRC-2 · Chapter 7
Data - Collection and Representation MCQs with Answers
60 multiple-choice questions on Data - Collection and Representation for PRC-2 Quantitative Analysis for Business. Try each one before revealing the answer and explanation.
Practise this chapter interactivelyQuestion 1
Which of the following is the best example of continuous data?
- A) The exact number of employees working in a manufacturing plant.
- B) The precise weight of a shipment of raw materials in kilograms.
- C) The number of defective items found in a daily batch.
- D) The total number of branches a bank operates across the country.
Show answer & explanation
Answer: B) The precise weight of a shipment of raw materials in kilograms.
Continuous data can take any value within a given range and can be measured to any degree of accuracy, such as weight, height, or time. Options A, C, and D are examples of discrete data because they can only take distinct, whole numbers.
Question 2
When constructing a grouped frequency distribution, what is the mathematical difference between the upper class boundary and the lower class boundary called?
- A) Class mark
- B) Class limit
- C) Class width
- D) Class frequency
Show answer & explanation
Answer: C) Class width
The class width (or class interval size) is formally calculated as the mathematical difference between the exact upper class boundary and the lower class boundary of a specific group.
Question 3
In statistics, how is the 'relative frequency' of a specific class calculated?
- A) By adding the frequency of the current class to the previous class.
- B) By dividing the class frequency by the total frequency of all classes.
- C) By multiplying the class mark by the class frequency.
- D) By subtracting the lower class limit from the upper class limit.
Show answer & explanation
Answer: B) By dividing the class frequency by the total frequency of all classes.
Relative frequency represents the proportion of data that falls into a particular class. It is determined by dividing the frequency of that specific class by the total sum of frequencies in the entire dataset.
Question 4
Which of the following graphical representations is specifically constructed by plotting cumulative frequencies?
- A) Histogram
- B) Pie Chart
- C) Ogive
- D) Bar Chart
Show answer & explanation
Answer: C) Ogive
An ogive is a cumulative frequency polygon. It is drawn by plotting the cumulative frequencies against the upper class boundaries of a dataset.
Question 5
A researcher conducts direct interviews with consumers to gather opinions on a new product. What type of data is being collected?
- A) Secondary data
- B) Primary data
- C) Continuous data
- D) Grouped data
Show answer & explanation
Answer: B) Primary data
Primary data is information collected firsthand by the researcher for a specific original purpose. Direct interviews, surveys, and focus groups are classic examples of primary data collection.
Question 6
In a stem-and-leaf display, the 'stem' typically represents which part of the numerical data?
- A) Only the decimal values.
- B) The final trailing digit.
- C) The leading digit(s) of the data values.
- D) The frequency of the data.
Show answer & explanation
Answer: C) The leading digit(s) of the data values.
In a standard stem-and-leaf plot, the 'stem' represents the leading digit or digits (like the tens place), while the 'leaf' represents the final trailing digit (like the units place).
Question 7
Given the class interval '40 - 49' in a continuous dataset, what is the exact midpoint (class mark)?
- A) 44.5
- B) 45.0
- C) 44.0
- D) 49.5
Show answer & explanation
Answer: A) 44.5
The class mark (midpoint) is calculated by adding the lower limit and upper limit, then dividing by two. (40 + 49) / 2 = 89 / 2 = 44.5.
Question 8
Which specific statistical measure can be visually estimated by locating the 50% mark on the y-axis of a cumulative frequency ogive?
- A) Mean
- B) Median
- C) Mode
- D) Standard Deviation
Show answer & explanation
Answer: B) Median
Because an ogive maps the accumulation of data, drawing a horizontal line from the 50% mark (the middle of the total frequency) to the curve, and then dropping down to the x-axis, accurately estimates the median.
Question 9
When drawing a pie chart to represent regional sales, if Region A accounts for Rs. 250,000 out of a total Rs. 1,000,000 in sales, what is the angle of Region A's sector?
- A) 25 degrees
- B) 45 degrees
- C) 90 degrees
- D) 120 degrees
Show answer & explanation
Answer: C) 90 degrees
The formula for a pie chart sector angle is (Category Value / Total Value) * 360. Here, (250,000 / 1,000,000) * 360 = 0.25 * 360 = 90 degrees.
Question 10
What is the primary visual function of a standard histogram?
- A) To show the percentage distribution of qualitative data.
- B) To display the frequency distribution of continuous grouped data using adjacent vertical bars.
- C) To map out the relationship between two independent variables.
- D) To show cumulative totals over time.
Show answer & explanation
Answer: B) To display the frequency distribution of continuous grouped data using adjacent vertical bars.
A histogram is a graphical representation of grouped continuous data. It uses adjacent vertical bars where the area of each bar is proportional to the frequency of that specific class.
Question 11
If a researcher utilizes data originally published in an economic journal from a decade ago, this data is classified as:
- A) Primary data
- B) Secondary data
- C) Ungrouped data
- D) Subjective data
Show answer & explanation
Answer: B) Secondary data
Secondary data is information that was already collected by someone else for another purpose and published previously, such as reports in journals, government census databases, or historical books.
Question 12
In a box and whisker plot, the central box visually represents which portion of the dataset?
- A) The entire range from minimum to maximum.
- B) The interquartile range (the middle 50% of the data).
- C) The highest 25% of the data.
- D) The standard deviation.
Show answer & explanation
Answer: B) The interquartile range (the middle 50% of the data).
The 'box' in a box and whisker plot spans from the first quartile (Q1) to the third quartile (Q3), visually highlighting the interquartile range, which contains the middle 50% of the data values.
Question 13
A raw list of unstructured, unorganized numbers collected from an initial survey is referred to as:
- A) Arrayed data
- B) Ungrouped data
- C) Continuous variables
- D) A frequency polygon
Show answer & explanation
Answer: B) Ungrouped data
Raw data that has just been collected and has not yet been sorted, arrayed, or structured into frequency distribution classes is known strictly as ungrouped data.
Question 14
Consider a stem-and-leaf plot where the stem is '6' and the associated leaves are '2, 5, 8'. What actual data points does this represent?
- A) 6, 2, 5, 8
- B) 6.2, 6.5, 6.8
- C) 62, 65, 68
- D) 26, 56, 86
Show answer & explanation
Answer: C) 62, 65, 68
In a traditional stem-and-leaf setup for two-digit integers, the stem represents the tens digit (6) and the leaves represent the ones digit, resulting in the distinct values 62, 65, and 68.
Question 15
Which of the following charts is most appropriate for displaying categorical (qualitative) data to show parts of a whole?
- A) Histogram
- B) Ogive
- C) Pie Chart
- D) Frequency Polygon
Show answer & explanation
Answer: C) Pie Chart
A pie chart breaks down a whole circle into 'slices' based on categories, making it the ideal choice for displaying how different qualitative categories contribute to a total percentage.
Question 16
Which of the following is an example of continuous data?
- A) The number of employees in a firm
- B) The number of chairs in a room
- C) The height of a commercial building
- D) The number of cars in a parking lot
Show answer & explanation
Answer: C) The height of a commercial building
Continuous data represents variables that can assume any possible fractional value within a given specific range, such as the exact height of a building.
Question 17
Data that is systematically collected and tracked over a specified period of time is referred to as:
- A) Discrete data
- B) Cross-sectional data
- C) Time series data
- D) Grouped data
Show answer & explanation
Answer: C) Time series data
Time series data are explicitly defined as data values that are collected and tracked sequentially over a period of time.
Question 18
Which of the following statements regarding discrete data classes is true?
- A) There is absolutely no gap between them.
- B) There are natural gaps between them.
- C) They must be measured in decimals.
- D) They are plotted as ogives only.
Show answer & explanation
Answer: B) There are natural gaps between them.
A grouped frequency distribution of discrete data inherently has defined gaps between the designated classes.
Question 19
In standard statistical class boundaries, which of the following characteristics strictly applies?
- A) There are distinct gaps between classes.
- B) There is absolutely no gap between the classes.
- C) They cannot be plotted on a graph.
- D) They only apply to qualitative data.
Show answer & explanation
Answer: B) There is absolutely no gap between the classes.
Unlike discrete data limits, in continuous class boundaries, there is mathematically no gap between the consecutive classes.
Question 20
What does a single point plotted on a "less than" ogive curve specifically indicate?
- A) The exact mean of the data.
- B) How many observations have a value less than the corresponding value on the x-axis.
- C) The variance of the sample.
- D) The maximum frequency of the data.
Show answer & explanation
Answer: B) How many observations have a value less than the corresponding value on the x-axis.
Each point on an ogive curve visually shows how many units or observations had values strictly less than the corresponding data value plotted on the axis.
Question 21
Which of the following is a classic example of discrete data?
- A) The exact weight of a vegetable bag
- B) The precise length of a metal rod
- C) The number of seats available in a conference room
- D) The temperature of a room
Show answer & explanation
Answer: C) The number of seats available in a conference room
Discrete data consists of countable, whole numbers that cannot be broken into fractions, such as the exact number of seats in a room.
Question 22
How is a "more than" ogive graphically developed?
- A) By plotting standard relative frequencies.
- B) By utilizing a more than cumulative frequency series.
- C) By drawing independent bars instead of continuous lines.
- D) By plotting only the highest values.
Show answer & explanation
Answer: B) By utilizing a more than cumulative frequency series.
While a standard ogive is a "less than" curve, a "more than" ogives graph is developed specifically by calculating and using a more than cumulative frequency series.
Question 23
If a frequency distribution table shows weekly sales of "400 to under 500" with a cumulative frequency reaching 40, what does this 40 represent?
- A) The absolute total sales value.
- B) The running total of frequencies up to and including that class.
- C) The mean weekly sales.
- D) The class width of the final group.
Show answer & explanation
Answer: B) The running total of frequencies up to and including that class.
The cumulative frequency represents the running mathematical total of all combined frequencies up to the upper boundary of that specific class.
Question 24
Cross-sectional data is best described as:
- A) Data collected over consecutive time periods.
- B) Data collected at a single point in time across various subjects.
- C) Data that only contains continuous variables.
- D) Data representing endless infinite progressions.
Show answer & explanation
Answer: B) Data collected at a single point in time across various subjects.
While time series data is tracked chronologically over time, cross-sectional data captures a snapshot of multiple subjects at one single, specific point in time.
Question 25
The term 'frequency' in a grouped distribution refers to:
- A) The mathematical difference between the highest and lowest value.
- B) The number of times a specific value or class of values occurs.
- C) The exact midpoint of a class.
- D) The cumulative total of the entire dataset.
Show answer & explanation
Answer: B) The number of times a specific value or class of values occurs.
Frequency is strictly defined as the count of occurrences or total observations that fall within a defined data class interval.
Question 26
To find the precise class mark or mid-point of a grouped class, a researcher must:
- A) Subtract the lower limit from the upper limit.
- B) Add the upper and lower limits and divide by two.
- C) Multiply the upper and lower limits.
- D) Divide the frequency by two.
Show answer & explanation
Answer: B) Add the upper and lower limits and divide by two.
The mid-point of a given class is calculated mathematically by taking the average of the upper and lower limits of that specific class.
Question 27
Which type of data variable can naturally assume any fractional value within a given specific range?
- A) Discrete variable
- B) Continuous variable
- C) Qualitative variable
- D) Categorical variable
Show answer & explanation
Answer: B) Continuous variable
Examples of continuous data, like height or weight, demonstrate that these variables can be measured to take any precise decimal value within a range.
Question 28
If an observer wishes to convert discrete grouped data limits into continuous class boundaries, what mathematical adjustment is primarily made?
- A) Completely removing the class limits.
- B) Closing the gaps between the consecutive classes.
- C) Adding the absolute frequencies together.
- D) Squaring the data values.
Show answer & explanation
Answer: B) Closing the gaps between the consecutive classes.
Discrete data can be formally converted into continuous data by adjusting the limits to boundaries, thereby closing and removing the gaps between classes.
Question 29
Which data type is intrinsically countable rather than measurable?
- A) Continuous data
- B) Discrete data
- C) Time series data
- D) Cross-sectional data
Show answer & explanation
Answer: B) Discrete data
Discrete data represents countable whole items, such as the number of seats or students, whereas continuous data is measured with precision tools.
Question 30
When constructing an ogive, the cumulative frequency is traditionally plotted on which axis?
- A) The horizontal x-axis
- B) The vertical y-axis
- C) The secondary z-axis
- D) It is not plotted on an axis
Show answer & explanation
Answer: B) The vertical y-axis
In a standard cumulative frequency graph (ogive), the accumulated frequencies are always plotted ascending along the vertical y-axis.
Question 31
In a standard 'less than' cumulative frequency ogive, which specific values are plotted along the horizontal x-axis?
- A) The class midpoints (class marks).
- B) The lower class boundaries.
- C) The upper class boundaries.
- D) The absolute class frequencies.
Show answer & explanation
Answer: C) The upper class boundaries.
A 'less than' ogive graphically plots the cumulative frequencies against the upper boundaries of each class, representing the total number of observations falling below that specific upper limit.
Question 32
When constructing a box-and-whisker plot, the central rectangular 'box' visually represents which statistical measure?
- A) The total range of the dataset.
- B) The interquartile range (IQR), containing the middle 50% of the data.
- C) The variance of the sample.
- D) The standard error of the mean.
Show answer & explanation
Answer: B) The interquartile range (IQR), containing the middle 50% of the data.
In a box-and-whisker plot, the central box spans from the lower quartile (Q1) to the upper quartile (Q3), visually representing the interquartile range where the middle 50% of the observations lie.
Question 33
In a stem-and-leaf display, what does the 'leaf' typically represent for a given data point?
- A) The leading leading digit(s) of the value.
- B) The absolute frequency of the value.
- C) The final, trailing digit of the data value.
- D) The median of the specific row.
Show answer & explanation
Answer: C) The final, trailing digit of the data value.
In a stem-and-leaf plot, the 'stem' represents the leading digits (e.g., the tens place), while the 'leaf' represents the final trailing digit (e.g., the ones place) for each individual observation.
Question 34
What is the primary structural difference between a standard bar chart and a histogram?
- A) Histograms are used for qualitative data, while bar charts are used for quantitative data.
- B) Bar charts strictly plot cumulative frequencies.
- C) Histograms are drawn with no gaps between the bars to represent continuous grouped data, whereas bar charts have distinct gaps.
- D) Histograms use circles instead of bars.
Show answer & explanation
Answer: C) Histograms are drawn with no gaps between the bars to represent continuous grouped data, whereas bar charts have distinct gaps.
Histograms visually represent continuous frequency distributions using class boundaries, meaning the bars touch each other without gaps. Bar charts represent discrete or categorical data and feature distinct gaps between the bars.
Question 35
A researcher utilizes population demographics published by the National Bureau of Statistics to conduct an economic analysis. This data is formally classified as:
- A) Primary Data
- B) Secondary Data
- C) Experimental Data
- D) Unbounded Data
Show answer & explanation
Answer: B) Secondary Data
Secondary data is data that was originally collected by someone else (like a government agency or another researcher) for a different primary purpose, but is being reused by the current analyst.
Question 36
In a pie chart representing a company's total expenses, if 'Rent' constitutes exactly 15% of the total costs, what will be the degree measure of its central angle?
- A) 15 degrees
- B) 30 degrees
- C) 54 degrees
- D) 90 degrees
Show answer & explanation
Answer: C) 54 degrees
A full pie chart represents 360 degrees. To find the angle for a specific component, multiply its percentage by 360. 0.15 * 360 = 54 degrees.
Question 37
When drawing a frequency polygon, the data points are mathematically plotted at the intersection of the frequencies and the:
- A) Lower class limits
- B) Upper class boundaries
- C) Class midpoints (class marks)
- D) Cumulative percentages
Show answer & explanation
Answer: C) Class midpoints (class marks)
A frequency polygon is created by plotting coordinate points at the exact midpoints of each class interval (which corresponds to the top center of each histogram bar) and connecting them with straight lines.
Question 38
Which of the following describes qualitative data that can be logically arranged into a meaningful sequence or ranking?
- A) Nominal data
- B) Continuous data
- C) Ordinal data
- D) Time series data
Show answer & explanation
Answer: C) Ordinal data
Ordinal data is a type of qualitative (categorical) data that possesses a natural, logical order or ranking, such as survey responses ranging from 'Poor' to 'Excellent'.
Question 39
In a frequency distribution featuring unequal class intervals, the height of a bar in a histogram must be rendered proportional to its:
- A) Absolute frequency
- B) Frequency density
- C) Class midpoint
- D) Standard deviation
Show answer & explanation
Answer: B) Frequency density
When class widths are unequal, plotting raw frequencies heavily distorts the visual area. To correct this, the height of the bars must represent the 'frequency density' (Frequency / Class Width).
Question 40
The very last value calculated in a 'less than' cumulative frequency distribution column will logically always equal:
- A) The mean of the dataset.
- B) Exactly 100.
- C) The total number of observations (N) in the entire dataset.
- D) The maximum class boundary.
Show answer & explanation
Answer: C) The total number of observations (N) in the entire dataset.
Because a 'less than' cumulative frequency column maintains a running total of all observations, the final class will inevitably encompass every single observation, equaling the total sample size (N).
Question 41
Which specific graphical chart is best utilized to compare the varied components of two or more different categorical variables side-by-side?
- A) A simple frequency polygon
- B) A multiple bar chart
- C) A 'less than' ogive
- D) A scatter diagram
Show answer & explanation
Answer: B) A multiple bar chart
A multiple bar chart (or clustered bar chart) places bars representing different categories or years directly next to one another, making it highly effective for visual side-by-side comparisons.
Question 42
When raw, unorganized statistical data is manually arranged into ascending or descending order, the resulting structured format is called an:
- A) Ogive
- B) Array
- C) Aggregate
- D) Index
Show answer & explanation
Answer: B) Array
An array is the simplest method of organizing raw data, achieved simply by sorting the individual numerical values sequentially from smallest to largest (or vice versa).
Question 43
Visually, a standard 'more than' ogive graph generally slopes in which direction?
- A) Upward from left to right.
- B) Downward from left to right.
- C) Horizontally straight.
- D) Vertically straight.
Show answer & explanation
Answer: B) Downward from left to right.
Because it begins with the total number of observations (N) and subtracts frequencies as it moves through higher classes, a 'more than' cumulative frequency ogive always slopes downward.
Question 44
Why are strict 'class boundaries' established for grouped continuous data?
- A) To ensure there are distinct, countable gaps between consecutive classes.
- B) To mathematically eliminate any gaps between consecutive classes, ensuring continuity.
- C) To find the median quickly.
- D) To convert nominal data into interval data.
Show answer & explanation
Answer: B) To mathematically eliminate any gaps between consecutive classes, ensuring continuity.
Class boundaries extend the discrete class limits by half a unit in both directions, mathematically closing the gap between classes so that continuous variables can be properly categorized without falling between groups.
Question 45
Which of the following variables would strictly be classified as a discrete quantitative variable?
- A) The exact speed of a moving train.
- B) The volume of water in a reservoir.
- C) The number of active bank accounts held by a customer.
- D) The physical length of a produced textile.
Show answer & explanation
Answer: C) The number of active bank accounts held by a customer.
The number of bank accounts is a countable, discrete whole number. It is logically impossible to hold 2.75 bank accounts. Speed, volume, and length are measured continuously.
Question 46
A financial analyst collects annual sales data directly through a series of newly conducted field surveys and interviews with store managers. This data is formally classified as:
- A) Secondary Data
- B) Primary Data
- C) Continuous Data
- D) Discrete Grouped Data
Show answer & explanation
Answer: B) Primary Data
Primary data is defined as fresh, original data collected firsthand by the researcher for a specific, targeted purpose, such as conducting direct field surveys.
Question 47
In a pie chart illustrating a company's revenue streams, if 'Software Sales' represent exactly 35% of the total revenue, what is the precise degree measure of its central angle?
- A) 35 degrees
- B) 70 degrees
- C) 126 degrees
- D) 150 degrees
Show answer & explanation
Answer: C) 126 degrees
A full pie chart represents exactly 360 degrees. To calculate the central angle for a specific segment, multiply its percentage by 360. Here, 0.35 * 360 = 126 degrees.
Question 48
What mathematical procedure is used to calculate the 'class mark' (mid-point) of a specific frequency distribution class?
- A) Subtracting the lower limit from the upper limit.
- B) Adding the upper and lower limits and dividing by two.
- C) Multiplying the frequency by the class width.
- D) Dividing the cumulative frequency by two.
Show answer & explanation
Answer: B) Adding the upper and lower limits and dividing by two.
The class mark, or mid-point, represents the exact center of a class interval and is calculated by adding the lower class limit to the upper class limit and strictly dividing the sum by 2.
Question 49
What is the defining visual difference between a histogram and a standard bar chart?
- A) A histogram is utilized exclusively for qualitative nominal data.
- B) Bar charts strictly plot cumulative percentages.
- C) Histograms represent continuous grouped data without gaps between the columns, while bar charts feature distinct gaps.
- D) Histograms must always be drawn horizontally.
Show answer & explanation
Answer: C) Histograms represent continuous grouped data without gaps between the columns, while bar charts feature distinct gaps.
Because histograms plot continuous class boundaries, their rectangular bars physically touch. Bar charts are used for discrete or categorical variables and therefore contain spacing between the bars.
Question 50
When constructing a 'less than' cumulative frequency ogive, the cumulative frequencies are plotted against which specific values on the x-axis?
- A) The class mid-points
- B) The lower class boundaries
- C) The upper class boundaries
- D) The absolute raw frequencies
Show answer & explanation
Answer: C) The upper class boundaries
A 'less than' ogive fundamentally plots the running cumulative frequency against the upper boundary of each class, visually showing how many total observations fall strictly below that upper threshold.
Question 51
Which of the following variables serves as a textbook example of a continuous quantitative variable?
- A) The number of chairs in a conference room.
- B) The precise weight of a freight shipment in kilograms.
- C) The total number of employees working in a department.
- D) The number of defective components on an assembly line.
Show answer & explanation
Answer: B) The precise weight of a freight shipment in kilograms.
Continuous data can assume any possible fractional or decimal value within a given measurement range. Physical measurements like weight, height, and temperature are continuous variables.
Question 52
In a statistical cumulative frequency table, what does the final, bottom-most value in the cumulative frequency column always mathematically equal?
- A) The arithmetic mean of the distribution.
- B) Exactly 100%.
- C) The total number of observations (N) in the entire dataset.
- D) The standard error.
Show answer & explanation
Answer: C) The total number of observations (N) in the entire dataset.
Because cumulative frequency maintains a running sum of all observations as you progress through the classes, the final class encompasses every single data point, equaling the total sample size (N).
Question 53
When interpreting a standard 'stem-and-leaf' plot, what does the 'stem' generally represent?
- A) The single trailing digit of the data value.
- B) The frequency of that specific class.
- C) The leading digit(s) of the data values.
- D) The absolute maximum outlier.
Show answer & explanation
Answer: C) The leading digit(s) of the data values.
In a stem-and-leaf diagram, the 'stem' clusters the data by its leading digits (e.g., the tens or hundreds place), while the 'leaf' displays the final trailing digit for individual observations.
Question 54
In a box-and-whisker plot, the central rectangular box graphically spans the distance between:
- A) The absolute minimum and absolute maximum values.
- B) The mean and the median.
- C) The lower quartile (Q1) and the upper quartile (Q3).
- D) The standard deviation limits.
Show answer & explanation
Answer: C) The lower quartile (Q1) and the upper quartile (Q3).
The central box in a box-and-whisker plot specifically represents the Interquartile Range (IQR), visually stretching from Q1 (25th percentile) to Q3 (75th percentile), containing the middle 50% of the data.
Question 55
If raw statistical data is manually sorted from smallest to largest value, the resulting structured presentation is called an:
- A) Ogive
- B) Array
- C) Aggregate sequence
- D) Unbounded matrix
Show answer & explanation
Answer: B) Array
An array is the simplest and most fundamental form of organized data, achieved by explicitly sorting individual numerical observations into either ascending or descending mathematical order.
Question 56
Visually, how does a 'more than' cumulative frequency ogive plot consistently slope?
- A) It slopes strictly upward from left to right.
- B) It slopes strictly downward from left to right.
- C) It remains perfectly horizontal.
- D) It forms a symmetrical bell curve.
Show answer & explanation
Answer: B) It slopes strictly downward from left to right.
Because a 'more than' cumulative frequency ogive begins with the total sample size (N) and subtracts frequencies as it moves across higher boundary thresholds, the curve inherently slopes downward.
Question 57
What is the primary statistical purpose of converting discrete 'class limits' into continuous 'class boundaries'?
- A) To calculate the arithmetic mean faster.
- B) To mathematically close the gaps between consecutive classes, ensuring continuity for graphing tools like histograms.
- C) To convert quantitative data into qualitative categories.
- D) To double the standard error.
Show answer & explanation
Answer: B) To mathematically close the gaps between consecutive classes, ensuring continuity for graphing tools like histograms.
Class boundaries are formed by extending the limits by half a unit (e.g., 9.5 to 19.5), which completely eliminates gaps between classes, allowing continuous data to be plotted without interruption.
Question 58
Data collected representing customer satisfaction ratings categorized as 'Poor', 'Fair', 'Good', and 'Excellent' is classified mathematically as:
- A) Continuous data
- B) Nominal data
- C) Ordinal data
- D) Time series data
Show answer & explanation
Answer: C) Ordinal data
Ordinal data is a sub-type of qualitative (categorical) data that possesses a distinct, logical ranking or order, such as a progression from 'Poor' up to 'Excellent'.
Question 59
Statistical data gathered from multiple different corporations representing their exact net profit for the year ending 2024 is an example of:
- A) Time series data
- B) Cross-sectional data
- C) Continuous progression data
- D) Predictive regression data
Show answer & explanation
Answer: B) Cross-sectional data
Data collected across a variety of different subjects (like multiple companies or regions) at one single, specific point in time is technically defined as cross-sectional data.
Question 60
In a histogram featuring unequal class widths, what metric must govern the physical height of the rectangular bars to prevent visual distortion?
- A) Raw absolute frequency
- B) Cumulative percentage
- C) Frequency density
- D) The class mid-point
Show answer & explanation
Answer: C) Frequency density
When class intervals are not uniform, plotting raw frequency heavily distorts the visual area. To accurately represent the data, the height of the bars must represent the frequency density (Frequency / Class Width).