Why is the median resistant, but the mean is not?
Table of contents
- 1. Intro to Stats and Collecting Data1h 14m
- 2. Describing Data with Tables and Graphs1h 55m
- 3. Describing Data Numerically2h 5m
- 4. Probability2h 16m
- 5. Binomial Distribution & Discrete Random Variables3h 6m
- 6. Normal Distribution and Continuous Random Variables2h 11m
- 7. Sampling Distributions & Confidence Intervals: Mean3h 23m
- Sampling Distribution of the Sample Mean and Central Limit Theorem19m
- Distribution of Sample Mean - Excel23m
- Introduction to Confidence Intervals15m
- Confidence Intervals for Population Mean1h 18m
- Determining the Minimum Sample Size Required12m
- Finding Probabilities and T Critical Values - Excel28m
- Confidence Intervals for Population Means - Excel25m
- 8. Sampling Distributions & Confidence Intervals: Proportion1h 25m
- 9. Hypothesis Testing for One Sample3h 29m
- 10. Hypothesis Testing for Two Samples4h 50m
- Two Proportions1h 13m
- Two Proportions Hypothesis Test - Excel28m
- Two Means - Unknown, Unequal Variance1h 3m
- Two Means - Unknown Variances Hypothesis Test - Excel12m
- Two Means - Unknown, Equal Variance15m
- Two Means - Unknown, Equal Variances Hypothesis Test - Excel9m
- Two Means - Known Variance12m
- Two Means - Sigma Known Hypothesis Test - Excel21m
- Two Means - Matched Pairs (Dependent Samples)42m
- Matched Pairs Hypothesis Test - Excel12m
- 11. Correlation1h 24m
- 12. Regression1h 50m
- 13. Chi-Square Tests & Goodness of Fit2h 21m
- 14. ANOVA1h 57m
3. Describing Data Numerically
Mean
Problem 6.1.17c
Textbook Question
[NW] [DATA] TelevisionsIn the Sullivan Statistics Survey I, individuals were asked to disclose the number of televisions in their household. In the following probability distribution, the random variable X represents the number of televisions in households.

c. Calculate and explain the mean of the random variable X.
Verified step by step guidance1
Identify the random variable X, which represents the number of televisions in a household, and the corresponding probabilities P(x) for each value of X from the table.
Recall that the mean (or expected value) of a discrete random variable X is calculated using the formula:
\[\text{Mean} = E(X) = \sum (x \times P(x))\]
where the sum is taken over all possible values of x.
Multiply each value of x (number of televisions) by its corresponding probability P(x) from the table. For example, calculate 0 \times 0, 1 \times 0.161, 2 \times 0.261, and so on for all values of x.
Add all the products obtained in the previous step to get the sum \( \sum (x \times P(x)) \). This sum represents the mean number of televisions per household.
Interpret the mean as the average number of televisions in a household based on the given probability distribution, which provides a measure of central tendency for the random variable X.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Random Variable
A random variable is a numerical outcome of a random phenomenon. In this context, X represents the number of televisions in a household, which can take on discrete values from 0 to 9. Understanding the random variable helps in analyzing the distribution of possible outcomes.
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Intro to Random Variables & Probability Distributions
Probability Distribution
A probability distribution assigns probabilities to each possible value of a random variable, showing how likely each outcome is. Here, P(x) gives the probability that a household has x televisions. The sum of all probabilities must equal 1, ensuring a complete description of all outcomes.
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Calculating Probabilities in a Binomial Distribution
Mean (Expected Value) of a Discrete Random Variable
The mean or expected value is the weighted average of all possible values of the random variable, calculated by summing the products of each value and its probability. It represents the long-run average number of televisions per household in this survey.
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Expected Value (Mean) of Random Variables
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