/*! 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 1 You are given \(n=5\) measuremen... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

You are given \(n=5\) measurements: 0,5,1,1,3 . a. Draw a dotplot for the data. (HINT: If two measurements are the same, place one dot above the other.) Guess the approximate "center." b. Find the mean, median, and mode. c. Locate the three measures of center on the dotplot in part a. Based on the relative positions of the mean and median, are the measurements symmetric or skewed?

Short Answer

Expert verified
If skewed, is it positively or negatively skewed?

Step by step solution

01

Draw a dotplot for the given data and guess the approximate center

Run the dataset in ascending order: 0, 1, 1, 3, 5. Next, draw a dotplot with the data points on a number line and stack the dots if the data points are repeated.
02

Calculate the mean, median, and mode

Calculate the mean by finding the sum of the data points and dividing by the total number of values (n = 5). The median is the middle value of the dataset. If the dataset has an even number of values, the median is the average of the two middle values. The mode is the most frequently occurring value(s) in the dataset.
03

Locate the mean, median, and mode on the dotplot

Illustrate the mean, median, and mode on the dotplot created in Step 1. Based on their positions, determine if the dataset is symmetric or skewed.
04

Determine if the dataset is symmetric or skewed

A dataset is considered symmetric if the mean and median are similar or equal. It is skewed if the mean is greater than the median (positively skewed) or if the mean is less than the median (negatively skewed).

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.

Dotplot
A dotplot is a simple graphical representation used to visualize the frequency of data points. It consists of a number line where each data value is represented by a dot. If a value occurs more than once, dots are stacked vertically. This type of chart provides an easy way to see the distribution and concentration of values, which helps in identifying patterns such as clustering, gaps, and outliers. To create a dotplot for the given data set (0,1,1,3,5), you need to place a dot for each measurement on the number line at the appropriate value, stacking the dots for the repeated value of 1.

By examining the dotplot, you can make an educated guess about the approximate 'center' or typical value of the dataset. This estimated center can later be compared to the calculated measures of central tendency such as mean, median, and mode to verify its accuracy.
Mean
The mean, often referred to as the average, is a measure of central tendency calculated by dividing the sum of all values in a dataset by the number of values. For our dataset of five measurements (0,1,1,3,5), the mean is computed by adding these numbers and dividing the total by 5, the number of measurements. You sum up 0 + 1 + 1 + 3 + 5 to get 10, and then divide by 5 to find a mean of 2. This tells us that on average, the dataset centers around the value 2. While the mean provides a quick snapshot of the data's center, it is sensitive to extreme values or outliers, which can skew the result.
Median
The median is the value that falls in the middle of your dataset when it is arranged in ascending order, effectively splitting the dataset into two equal halves. If the dataset has an odd number of values, the median is simply the middle value. For an even number of values, the median is calculated as the average of the two middle values. With our dataset (0,1,1,3,5), the middle value is 1, making it the median. Unlike the mean, the median is not affected by outliers and is therefore considered a more robust measure of central tendency for skewed distributions.
Mode
The mode is the most frequently occurring value within a dataset. A dataset may have one mode, more than one mode, or no mode at all depending on the frequency of individual data points. For the dataset given (0,1,1,3,5), the number 1 appears more frequently than the others, occurring twice. Therefore, 1 is the mode. Understanding the mode is particularly useful for categorical data where mean and median cannot be defined, and it also highlights the most common value in a dataset with numerical values.
Data Skewness
Skewness is a descriptor of the asymmetry in the distribution of data values. When the mean and median are equal or close, the data is generally symmetrical. If there's a significant difference between the mean and median, the data is likely skewed. Positive skewness (or right skew) means the mean is greater than the median, often due to outliers on the higher end of the scale. Negative skewness (or left skew) occurs when the mean is less than the median, which can happen due to outliers at the lower end. In our example dataset (0,1,1,3,5), the mean is 2, and the median is 1, suggesting a slight positive skewness due to the presence of the high value of 5, which pulls the mean to the right.

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 random sample of 100 foxes was examined by a team of veterinarians to determine the prevalence of a particular type of parasite. Counting the number of parasites per fox, the veterinarians found that 69 foxes had no parasites, 17 had one parasite, and so on. A frequency tabulation of the data is given here: $$ \begin{array}{l|rrrrrrrrr} \text { Number of Parasites, } x & 0 & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 \\ \hline \text { Number of Foxes, } f & 69 & 17 & 6 & 3 & 1 & 2 & 1 & 0 & 1 \end{array} $$ a. Construct a relative frequency histogram for \(x\), the number of parasites per fox. b. Calculate \(\bar{x}\) and \(s\) for the sample. c. What fraction of the parasite counts fall within two standard deviations of the mean? Within three standard deviations? Do these results agree with Tchebysheff's Theorem? With the Empirical Rule?

The DVD player is a common fixture in most American households. In fact, most American households have DVDs, and many have more than one. A sample of 25 households produced the following measurements on \(x\), the number of DVDs in the household: $$ \begin{array}{lllll} 1 & 0 & 2 & 1 & 1 \\ 1 & 0 & 2 & 1 & 0 \\ 0 & 1 & 2 & 3 & 2 \\ 1 & 1 & 1 & 0 & 1 \\ 3 & 1 & 0 & 1 & 1 \end{array} $$ a. Is the distribution of \(x\), the number of DVDs in a household, symmetric or skewed? Explain. b. Guess the value of the mode, the value of \(x\) that occurs most frequently. c. Calculate the mean, median, and mode for these measurements. d. Draw a relative frequency histogram for the data set. Locate the mean, median, and mode along the horizontal axis. Are your answers to parts a and b correct?

If you scored at the 69 th percentile on a placement test, how does your score compare with others?

Construct a box plot for these data and identify any outliers: $$ 3,9,10,2,6,7,5,8,6,6,4,9,22 $$

The length of time required for an automobile driver to respond to a particular emergency situation was recorded for \(n=10\) drivers. The times (in seconds) were \(.5, .8,1.1, .7, .6,\) .9, .7, .8, .7, .8 a. Scan the data and use the procedure in Section 2.5 to find an approximate value for \(s\). Use this value to check your calculations in part b. b. Calculate the sample mean \(\bar{x}\) and the standard deviation \(s\). Compare with part a.

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.