Measures of Central Tendency Quiz
38 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the name of the Greek capital letter that is pronounced "sigma" and means "sum of"?

Sigma

Which of the following is a measure of central tendency?

  • Mean
  • Median
  • Mode
  • All of the above (correct)

What is the formula for calculating the sample mean?

x = (x1 + x2 + ... + xn) / n

What is the formula for calculating the population mean?

<p>μ = Σx / n</p> Signup and view all the answers

What is the midpoint of a dataset called?

<p>Median</p> Signup and view all the answers

The median is not sensitive to changes in the dataset as long as the number of items in the dataset does not change.

<p>True (A)</p> Signup and view all the answers

What is the value that occurs most frequently in a dataset called?

<p>Mode</p> Signup and view all the answers

All datasets have a mode.

<p>False (B)</p> Signup and view all the answers

Which of the following is a measure of position?

<p>All of the above (D)</p> Signup and view all the answers

What is the midpoint of the first half of a dataset called?

<p>First quartile (Q1)</p> Signup and view all the answers

What is the midpoint of the second half of a dataset called?

<p>Third quartile (Q3)</p> Signup and view all the answers

The second quartile (Q2) is the same as the median.

<p>True (A)</p> Signup and view all the answers

What is the difference between the highest and lowest values in a dataset called?

<p>Range</p> Signup and view all the answers

What is the difference between the third and first quartiles called?

<p>Inter-quartile range</p> Signup and view all the answers

What is the average of the squared differences between the data values and the mean called?

<p>Population variance</p> Signup and view all the answers

What is the square root of the variance called?

<p>Standard deviation</p> Signup and view all the answers

The standard deviation controls the spread of a distribution.

<p>True (A)</p> Signup and view all the answers

What is the number of standard deviations from the mean called?

<p>Standard score (z-score)</p> Signup and view all the answers

What is the percent ratio of the standard deviation to the mean called?

<p>Coefficient of variation</p> Signup and view all the answers

The coefficient of variation is a very useful measure when the data are in different units or the data are in the same units, but the means are far apart.

<p>True (A)</p> Signup and view all the answers

What type of plot is used to graphically represent a dataset that contains a small number of values?

<p>Box and whisker plot (C)</p> Signup and view all the answers

In a symmetrical distribution, the median is near the center of the box and the whiskers are about the same length.

<p>True (A)</p> Signup and view all the answers

In positively skewed distribution, the median is more to the left of the center of the box, or the right whisker is larger than the left whisker.

<p>True (A)</p> Signup and view all the answers

In a negatively skewed distribution, the median is more to the right of the center of the box, or the left whisker is larger than the right whisker.

<p>True (A)</p> Signup and view all the answers

The area under the normal distribution curve is equal to 1.0 or 100%

<p>True (A)</p> Signup and view all the answers

The normal curve is asymptotic to the x-axis in both directions.

<p>True (A)</p> Signup and view all the answers

What is the mean of the standard normal distribution?

<p>0</p> Signup and view all the answers

What is the standard deviation of the standard normal distribution?

<p>1</p> Signup and view all the answers

The area under the normal distribution curve corresponds to a probability.

<p>True (A)</p> Signup and view all the answers

The standard deviation controls the spread of the normal distribution.

<p>True (A)</p> Signup and view all the answers

The normal curve is taller when the standard deviation is smaller and flatter, and wider when the standard deviation is larger.

<p>True (A)</p> Signup and view all the answers

What is the formula for standardizing a normally distributed variable?

<p>z = (x - μ) / σ</p> Signup and view all the answers

What is the standard score also known as?

<p>z-score</p> Signup and view all the answers

The area in the normal distribution table can be translated into probability by reading the value of the area in the normal distribution table.

<p>True (A)</p> Signup and view all the answers

The area or probability for a standard score of 4.0 is 1.0.

<p>True (A)</p> Signup and view all the answers

The area or probability for a standard score of -4.0 is 0.

<p>True (A)</p> Signup and view all the answers

When the value of the standard score is greater than 4.0, the area or probability is constant at 1.0.

<p>True (A)</p> Signup and view all the answers

When the value of the standard score is less than -4.0, the area or probability is constant at 0.

<p>True (A)</p> Signup and view all the answers

Flashcards

CamScanner

A mobile application for scanning documents and photos.

Mobile app

An application designed for phones or tablets.

Scanning

Converting a physical document to a digital image.

Document

A piece of paper with information.

Signup and view all the flashcards

Digital Image

An electronic representation of a picture or document.

Signup and view all the flashcards

Photo

A picture taken by a camera.

Signup and view all the flashcards

Application

A software program.

Signup and view all the flashcards

Convert

To change something from one form to another.

Signup and view all the flashcards

Mobile

Relating to or operating on mobile devices such as phones and tablets.

Signup and view all the flashcards

Electronic

Relating to or using electricity or electronics.

Signup and view all the flashcards

CamScanner function

A mobile app that digitizes physical documents.

Signup and view all the flashcards

Mobile document scanning

Using a phone app to convert paper to digital format.

Signup and view all the flashcards

Digitalization process

The act of turning physical material into a digital form.

Signup and view all the flashcards

Document digitization

Converting paper documents into computer files.

Signup and view all the flashcards

CamScanner features

Capabilities for scanning and storing documents.

Signup and view all the flashcards

App capabilities

Specific functionalities of a software program.

Signup and view all the flashcards

Digital storage

Saving documents in computer files.

Signup and view all the flashcards

Mobile scanning app

A software for converting hard copies to digital formats on a phone.

Signup and view all the flashcards

Document management

Organizing and storing digital documents efficiently.

Signup and view all the flashcards

Mobile document capture

Using mobile devices for grabbing and storing document pictures.

Signup and view all the flashcards

Study Notes

Measures of Central Tendency

  • There are three measures: mean, median, and mode
  • Mean (average): Sum of values divided by the number of values.
    • Population mean symbol: μ (mu)
    • Sample mean symbol: xÌ„ (x-bar)
    • Calculated on interval or ratio scales
    • Formula: xÌ„ = Σx / n (where Σx is the sum of all values, and n is the number of values)
    • Example calculation given in the text using a sample of cafeteria wait times (18, 25, 35, 30, 42, 28, 20, 15, 40, 38) resulting in a mean of 29.1 minutes
    • Disadvantage: Sensitive to outliers (extreme values)

Median

  • Midpoint of the data set, often used with skewed data
  • Not sensitive to changes in data as long as the number of items doesn't change.
  • Steps to find the median:
    • Arrange the data from lowest to highest
    • Identify the data value at the midpoint
    • If odd number of data points, the middle value is the median
    • If even number of data points, average the two middle values
  • Example using the data set: 12, 24, 18, 15, 21, 20, 23, 16, 19

Mode

  • Most frequently occurring value in a data set
  • Usually used for categorical data
  • Some data sets have no mode, or multiple modes
  • Not useful in further calculations

Measures of Position

  • Quartiles, Deciles, and Percentiles
  • Dividing data sets into parts
  • Quartiles divide a data set into four equal parts (Q1, Q2, Q3)
  • Q1: Midpoint of the first half of the data
  • Q2: Median
  • Q3: Midpoint of the second half of the data
  • Examples provided illustrating how to calculate quartiles and use of the data set (15 16 18 20 20 21 23 24 25 26 28 29 30)

Measures of Variability

  • Describe the amount of dispersion or spread in a data set

  • Examples include range, interquartile range, variance, and standard deviation

  • Range: Difference between the highest and lowest values. Example table showing range for major subjects and on-the-job training of students

  • Interquartile range: Difference between Q3 and Q1

  • Important to note that range and interquartile range are susceptible to extreme (or outlier) values in a data set

Coefficient of Variation

  • Useful measure when data are in different units or means are far apart; a percent ratio of standard deviation to the mean.

Box and Whisker Plots

  • Used for small data sets
  • Graphic representation of five specific data points: First quartile (Q1), Third quartile (Q3), Median, Lowest value (LV), Highest value (HV)
  • Helps visualize the distribution and identify skewness

The Normal Distribution

  • Symmetrical, bell-shaped probability distribution

  • Mean, median, and mode have the same value; the curve is asymptotic (i.e., the curve gets closer and closer to the x-axis but never touches the x-axis))

  • Total area under the curve is equal to 1.00 or 100%

  • Standard deviation controls the spread or width of the distribution

  • Standard normal distribution: Mean of 0 and standard deviation of 1; values are expressed in terms of z-scores - probabilities can be derived by reading from a table.

  • Examples relating to the use of mean, standard deviation, and z-scores for solving problems

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Stat-topics-MMW PDF

Description

Test your knowledge on the measures of central tendency, including mean, median, and mode. This quiz covers how to calculate these metrics, their symbols, advantages, and disadvantages, along with practical examples. Perfect for students looking to reinforce their understanding of statistics.

More Like This

Statistical Calculation Practice
10 questions
La Mediana e la Media Aritmetica
10 questions

La Mediana e la Media Aritmetica

AdvantageousDialogue5929 avatar
AdvantageousDialogue5929
Statistics: Mean and Median
6 questions
Use Quizgecko on...
Browser
Browser