/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 18 In a study of author productivit... [FREE SOLUTION] | 91Ó°ÊÓ

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In a study of author productivity ("Lotka's Test," Collection Mgmt., 1982: 111-118), a large number of authors were classified according to the number of articles they had published during a certain period. The results were presented in the accompanying frequency distribution: $$ \begin{aligned} &\text { Number }\\\ &\begin{array}{lrrrrrrrrr} \text { of papers } & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & \\ \text { Frequency } & 784 & 204 & 127 & 50 & 33 & 28 & 19 & 19 & \\ \text { Number } & & & & & & & & & \\ \text { of papers } & 9 & 10 & 11 & 12 & 13 & 14 & 15 & 16 & 17 \\ \text { Frequency } & 6 & 7 & 6 & 7 & 4 & 4 & 5 & 3 & 3 \end{array} \end{aligned} $$ a. Construct a histogram corresponding to this frequency distribution. What is the most interesting feature of the shape of the distribution? b. What proportion of these authors published at least five papers? At least ten papers? More than ten papers? c. Suppose the five \(15 \mathrm{~s}\), three \(16 \mathrm{~s}\), and three \(17 \mathrm{~s}\) had been lumped into a single category displayed as " \(\geq 15\)." Would you be able to draw a histogram? Explain. d. Suppose that instead of the values 15,16 , and 17 being listed separately, they had been combined into a 15-17 category with frequency 11 . Would you be able to draw a histogram? Explain.

Short Answer

Expert verified
Construct a histogram and proportion calculations. Histogram feasibility remains stable with grouped categories.

Step by step solution

01

Analyze the Frequency Distribution

Begin by interpreting the frequency distribution provided in the table. This includes the number of papers and their corresponding frequencies. We need to comprehend these as it forms the basis of our histogram.
02

Construct the Histogram

Plot the histogram using the frequency distribution. The x-axis should represent the number of papers, and the y-axis should represent the frequency. Bars will represent frequencies for each category. The most interesting feature is the rapid drop in frequency as the number of papers increases.
03

Calculate Proportions

To find the proportion of authors publishing at least five papers, sum the frequencies from papers 5 to 17, then divide by the total frequency. Do the same procedure separately for at least ten papers, and then for more than ten papers.
04

Interpret Histogram Feasibility with "≥15" Category

If the papers with frequencies corresponding to 15, 16, and 17 were combined into a single category "≥15", the histogram would have a bar for this range. The histogram remains drawable, but details regarding individual counts from 15 to 17 would be lost.
05

Interpret Histogram Feasibility with 15-17 Category

If papers 15, 16, and 17 were combined into a 15-17 category, resulting in a frequency of 11, the histogram can still be drawn. This simplifies the histogram slightly, preserving frequency detail while reducing category breadth.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Frequency Distribution Analysis
A frequency distribution is the organization of data to show how often each value in a set of data occurs. In this exercise, we have a frequency count of how many authors published different numbers of articles.
For instance, if a single paper category has a frequency of 784, it means 784 authors published one paper each during the study period, and so on for other numbers of papers.
Comprehensive analysis involves recognizing patterns in the data that can indicate trends or anomalies. In our dataset, the most prominent trend is the decline in the number of authors as the number of published papers increases. This decreasing trend is linear, showcasing that fewer authors manage to publish additional papers.
Proportion Calculation
Calculating proportions in frequency distribution helps us understand the relative quantities of different data segments.
  • For authors publishing at least five papers, we sum frequencies from 5 papers onward: 33 + 28 + 19 + 19 + 6 + 7 + 6 + 7 + 4 + 4 + 5 + 3 + 3 = 146. Then divide this by the total number of authors, which is 1,308 (the sum of all frequencies). This yields a proportion of 146/1308.

  • For calculations of at least ten papers, start summing from the frequency of 10 papers using: 7 + 6 + 7 + 4 + 4 + 5 + 3 + 3 = 39. Thus, 39/1308 is the proportion.

  • The computation for authors publishing more than ten papers starts from 11 papers and onward, using: 6 + 7 + 4 + 4 + 5 + 3 + 3 = 32. Therefore, the proportion is 32/1308.
Proportion calculations are great tools to discern more meaningful insights from the data.
Histogram Interpretation
When interpreting a histogram, you visually grasp data distribution.
Here, the histogram illustrates the number of authors versus the number of papers published, where the bars' heights reflect the frequency. The key insight from our histogram is the skewness as more authors write a smaller number of papers.
This pattern describes a long tail on the right, which emphasizes that a small group of authors are prolific. A correctly interpreted histogram can point out data trends and how closely distributed values are, while demonstrating central tendencies and variability in data.
Categorical Aggregation in Histograms
Categorical aggregation involves grouping data for simplicity.
For instance, in our exercise with the category ">=15," papers with frequencies 15, 16, and 17 are aggregated. This results in a single bar representing the frequency constituting the category.
While we lose some detail about individual frequency counts, the histogram remains intact with an overview of categories beyond a certain threshold.
If combined into a 15-17 category with frequency 11, rather than a ">=15," the bar represents all aggregates, achieving compact representation while retaining vital frequency information. Employing categorical aggregation in histograms allows easier data comprehension while maintaining essential distribution information.

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