Comparing & Displaying Quantitative Data Assessment Test

Quantitative data refers to information that can be measured and expressed numerically. This means that it can be assigned a numerical value and recorded. It is different from qualitative data, which is descriptive in nature and cannot be easily quantified. Therefore, the correct answer is that quantitative data can be measured and written down with numbers.

The stem and leaf display is a graphical representation that shows the distribution of a quantitative variable while preserving the individual values. It organizes the data by separating the leading digit(s) (the stem) from the trailing digit(s) (the leaf). Each stem corresponds to a range of values, and the leaves represent the individual data points within that range. This display allows for easy identification of the shape of the distribution, the range of values, and the individual data points.

The spread refers to the range of values observed in a data set. If the observations cover a wide range, it means that there is a large difference between the minimum and maximum values. Therefore, the correct answer is "Larger" as the spread is greater when the observations cover a wide range.

The softness of your cat is not a quantitative data because it cannot be measured or expressed in numerical terms. Quantitative data refers to information that can be measured or counted, such as the number of pennies, the age of your bike, or the amount of water in the ocean. However, the softness of your cat is a qualitative characteristic that is subjective and cannot be quantified.

Interviews are a source of quantitative data because they involve asking individuals a set of standardized questions and recording their responses in a structured manner. This allows for the collection of numerical data that can be analyzed statistically. By conducting interviews, researchers can gather quantitative information on various topics such as demographics, opinions, behaviors, and preferences.

Secondary data refers to data that has been collected by someone else for a different purpose. It includes sources like company reports, dairies, and written accounts, which are all historical records or documents. However, future events cannot be considered secondary data because they have not yet occurred and therefore cannot be collected or documented.

The given answer, "Time," is the correct answer because time is not a type of quantitative data. Quantitative data refers to numerical measurements or calculations that can be expressed in terms of quantity or amount. Time, on the other hand, is a unit of measurement used to quantify the duration or sequence of events and is not considered a numerical value or quantity in itself.

The given options are all methods of displaying quantitative data except for "Center charts". Center charts are not a commonly used method for displaying quantitative data. Dotplots, center plots, and line graphs are all commonly used methods for displaying quantitative data.

When comparing data sets, the features to focus on are spread, center, and shape. The amount is not a feature to consider when comparing data sets. The amount refers to the quantity or number of data points in a data set, which does not provide any information about the distribution or characteristics of the data. Therefore, it is not relevant when comparing data sets.

Dotplots are used to compare data sets by displaying the individual values as dots along a number line. When dotplots are positioned one above the other, it allows for easy visual comparison of the data sets. Each dotplot represents a different data set, and by positioning them vertically, it becomes clear how the data sets differ in terms of their distribution, central tendency, and variability. This arrangement also helps in identifying any overlapping or distinct patterns between the data sets.