/*! 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 58 "On the average day, about how m... [FREE SOLUTION] | 91Ó°ÊÓ

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"On the average day, about how many hours do you personally watch television?" Of 1,324 responses, the mode was 2 , the median was 2 , the mean was \(2.98,\) and the standard deviation was 2.66. Based on these statistics, what would you surmise about the shape of the distribution? Why? (Source: Data from CSM, UC Berkeley.)

Short Answer

Expert verified
The distribution is right-skewed due to the mean being larger than the median.

Step by step solution

01

Understanding the Mean, Median, and Mode

These measures of central tendency give us insight into the distribution. Here, the mean is \(2.98\), the median is \(2\), and the mode is \(2\). Since the mean is greater than the median, it suggests the presence of values higher than the median value, indicating a right-skewed distribution.
02

Analyzing the Standard Deviation

The standard deviation is \(2.66\), a relatively large value for a mean of \(2.98\). This suggests a wide spread of data points around the mean, which is typical for a distribution with skewness or outliers.
03

Considering the Mode and Median Together

Both the mode and the median are \(2\), indicating that \(2\) hours is the most frequently occurring and the middle value of the dataset respectively. Despite this, the higher mean suggests that the right tail extends more than the left tail, supporting the hypothesis of a right-skewed distribution.
04

Drawing Conclusion About the Distribution Shape

Considering all the statistics, the higher mean compared to the median indicates right skewness, suggesting that there are some individuals who watch significantly more TV than the average, pulling the mean higher. The mode being equal to the median reinforces the tendency of most respondents toward the lower side of the distribution.

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Key Concepts

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

Measure of Central Tendency
When we discuss data distribution, understanding the measures of central tendency is crucial. These measures include the mean, median, and mode. For this dataset:
  • The **mean** is the average value, which is calculated by summing all data points and dividing by the total number of data points. In this case, the mean is \(2.98\), suggesting that on average, respondents reported watching just under 3 hours of television per day.
  • The **median** is the middle value when the data points are arranged in order. Here, the median is \(2\), which indicates that half of the respondents watch more and half watch less.
  • The **mode** is the most frequently appearing value in a dataset. In this instance, the mode is \(2\), meaning that this is the most common response.
Together, these measures provide a snapshot of data behavior. They help indicate whether most values are clustered around a certain point or if the data is spread out. Differences between the mean and median can also hint at the distribution shape.
Right Skewed Distribution
In statistical terms, a distribution is right-skewed if it has a longer or fatter tail on the right side. This commonly occurs in datasets where some individuals have higher values than the majority. In our exercise, the mean of \(2.98\) being greater than the median and mode of \(2\) suggests this type of skewness. Frequently, in right-skewed distributions:
  • The majority of data points are clustered towards the lower end.
  • There may be a few exceptionally high values stretching the distribution to the right.
This means that even though most responses were around \(2\) hours, the few who watched significantly more TV effectively increased the overall average. These outliers are responsible for the mean being higher than the median. Thus, understanding right-skewed distributions is essential for interpreting unbalanced datasets where certain high values predominate and affect the overall mean.
Standard Deviation Analysis
Standard deviation measures data variability around the mean. A higher standard deviation denotes a wider spread of data points. For the TV watching data, the standard deviation is \(2.66\), which is quite large considering the mean is only \(2.98\).This significant deviation implies that while many respondents provided similar answers close to the mean, there are several responses far from it. This variability suggests that individuals have diverse viewing habits, ranging considerably from a few hours to potentially many more. Understanding standard deviation is essential because it tells us not only how tightly data points cluster around the mean but also how typical or atypical certain values are. In right-skewed distributions like this one, a higher standard deviation highlights the presence of those few high-value responses, confirming that our dataset includes considerable diversity in television watching habits.

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