/*! 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 27 A data set consists of 83 observ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A data set consists of 83 observations. How many classes would you recommend for a frequency distribution?

Short Answer

Expert verified
8 classes are recommended.

Step by step solution

01

Understand the Sturges' Rule

The number of classes for a frequency distribution can be determined using Sturges' Rule, which states that the number of classes \( k \) is approximately \( 1 + 3.322 \log_{10} n \), where \( n \) is the number of observations in the dataset.
02

Locate the Data

Identify the number of observations in your dataset, which is given as \( n = 83 \).
03

Calculate the Logarithm

Calculate \( \log_{10} 83 \). Using a calculator, we find that \( \log_{10} 83 \approx 1.9191 \).
04

Apply Sturges' Formula

Substitute \( n = 83 \) into the Sturges' formula:\[k = 1 + 3.322 \times \log_{10} 83 \approx 1 + 3.322 \times 1.9191 \approx 7.379\]
05

Round Up

Since the number of classes must be a whole number, round \( 7.379 \) up to the nearest whole number, which is 8.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

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

Sturges' Rule
When dealing with frequency distributions, determining the optimal number of classes is crucial for meaningful analysis. Sturges' Rule offers a straightforward guideline for this purpose. According to Sturges' Rule, the recommended number of classes \( k \) can be found using the formula:
  • \( k = 1 + 3.322 \log_{10} n \)
where \( n \) is the total number of observations in your dataset.

Sturges' Rule helps balance the detail of information with manageability. Too few classes may oversimplify the data, obscuring important features, while too many classes may complicate analysis without offering additional insights. It's important to remember that Sturges' Rule, while useful, is a guideline. The specific nature of your dataset might necessitate adjustments.
Number of Classes
The number of classes in a frequency distribution is a key element in data visualization. Using Sturges' Rule, you can calculate the ideal number of classes to effectively summarize your dataset. This involves substituting the number of observations \( n \) into the formula:
  • Determine \( \log_{10} n \)
  • Substitute the result into \( k = 1 + 3.322 \times \log_{10} n \)
  • Round up the result to the nearest whole number


Rounding up is mandatory since the number of classes must be a whole number. For instance, if your calculation results in a decimal, such as 7.379, you would round up to reach 8.

Choosing the right number of classes enhances the clarity of data presentation and ensures that important trends are not overlooked.
Data Set Observations
In any frequency distribution analysis, the initial step is understanding the number of observations in your data set, denoted as \( n \). The size of your data set influences how you interpret and apply Sturges' Rule.

For example, in a dataset with 83 observations, \( n = 83 \) guides the application of Sturges' formula. Larger datasets might require a different approach or confirmation that Sturges' Rule is appropriate. Similarly, smaller datasets may not need as many classes for practical analysis.

Understanding your data set is fundamental. It helps you employ statistical rules effectively and make informed decisions when summarizing and analyzing your data.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A chain of sport shops catering to beginning skiers, headquartered in Aspen, Colorado, plans to conduct a study of how much a beginning skier spends on his or her initial purchase of equipment and supplies. Based on these figures, it wants to explore the possibility of offering combinations, such as a pair of boots and a pair of skis, to induce customers to buy more. A sample of 44 cash register receipts revealed these initial purchases: $$\begin{array}{rrrrrrrrr}\$ 140 & \$ 82 & \$ 265 & \$ 168 & \$ 90 & \$ 114 & \$ 172 & \$ 230 & \$ 142 \\\86 & 125 & 235 & 212 & 171 & 149 & 156 & 162 & 118 \\\139 & 149 & 132 & 105 & 162 & 126 & 216 & 195 & 127 \\\161 & 135 & 172 & 220 & 229 & 129 & 87 & 128 & 126 \\\175 & 127 & 149 & 126 & 121 & 118 & 172 & 126 & \\\\\hline\end{array}$$ a. Arrive at a suggested class interval. b. Organize the data into a frequency distribution using a lower limit of \(\$ 70\). c. Interpret vour findings.

The Quick Change Oil Company has a number of outlets in the metropolitan Seattle area. The daily number of oil changes at the Oak Street outlet in the past 20 days are: $$\begin{array}{llllllllll}\hline 65 & 98 & 55 & 62 & 79 & 59 & 51 & 90 & 72 & 56 \\\70 & 62 & 66 & 80 & 94 & 79 & 63 & 73 & 71 & 85 \\\\\hline\end{array}$$ The data are to be organized into a frequency distribution. a. How many classes would you recommend? b. What class interval would you suggest? c. What lower limit would you recommend for the first class? d. Organize the number of oil changes into a frequency distribution. e. Comment on the shape of the frequency distribution. Also, determine the relative frequency distribution.

The manager of the BiLo Supermarket in Mt. Pleasant, Rhode Island, gathered the following information on the number of times a customer visits the store during a month. The responses of 51 customers were: $$\begin{array}{rrrrrrrrrrrrrrr}\hline 5 & 3 & 3 & 1 & 4 & 4 & 5 & 6 & 4 & 2 & 6 & 6 & 6 & 7 & 1 \\\1 & 14 & 1 & 2 & 4 & 4 & 4 & 5 & 6 & 3 & 5 & 3 & 4 & 5 & 6 \\\8 & 4 & 7 & 6 & 5 & 9 & 11 & 3 & 12 & 4 & 7 & 6 & 5 & 15 & 1 \\\1 & 10 & 8 & 9 & 2 & 12 & & & & & & & & & \\\\\hline\end{array}$$ a. Starting with 0 as the lower limit of the first class and using a class interval of 3 , organize the data into a frequency distribution. b. Describe the distribution. Where do the data tend to cluster? c. Convert the distribution to a relative frequency distribution.

The following data give the weekly amounts spent on groceries for a sample of 45 households. $$\begin{array}{|rrrrrrrrr|}\hline \$ 271 & \$ 363 & \$ 159 & \$ 76 & \$ 227 & \$ 337 & \$ 295 & \$ 319 & \$ 250 \\\279 & 205 & 279 & 266 & 199 & 177 & 162 & 232 & 303 \\\192 & 181 & 321 & 309 & 246 & 278 & 50 & 41 & 335 \\\116 & 100 & 151 & 240 & 474 & 297 & 170 & 188 & 320 \\\429 & 294 & 570 & 342 & 279 & 235 & 434 & 123 & 325 \\\\\hline\end{array}$$ a. How many classes would you recommend? b. What class interval would you suggest? c. What would you recommend as the lower limit of the first class? d. Organize the data into a frequency distribution.

Wachesaw Manufacturing Inc. produced the following number of units in the last 16 days. $$\begin{array}{llllllll}\hline 27 & 27 & 27 & 28 & 27 & 25 & 25 & 28 \\\26 & 28 & 26 & 28 & 31 & 30 & 26 & 26 \\\\\hline\end{array}$$ The information is to be organized into a frequency distribution. a. How many classes would you recommend? b. What class interval would you suggest? c. What lower limit would you recommend for the first class? d. Organize the information into a frequency distribution and determine the relative frequency distribution. e. Comment on the shape of the distribution.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.