Statistics Quiz on Variables and Distributions

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 definition of a variable in statistics?

  • A quantity that can take on different values.
  • A characteristic that is observable or measurable in every unit of the universe. (correct)
  • The average of a data set.
  • A set of all possible outcomes of an experiment.

What is the difference between a discrete random variable and a continuous random variable?

  • A discrete random variable can only take on a finite number of values, while a continuous random variable can take on an infinite number of values. (correct)
  • A discrete random variable is a subset of a sample space, while a continuous random variable is the entire sample space.
  • A discrete random variable is always measured in whole numbers, while a continuous random variable can be measured in fractions.
  • A discrete random variable is always measured with a unit, while a continuous random variable is unitless.

Which of the following is NOT a measure of central tendency?

  • Median
  • Variance (correct)
  • Mode
  • Mean

What does the probability mass function (pmf) represent?

<p>The probability distribution of a discrete random variable. (C)</p> Signup and view all the answers

What is the standard deviation of a normal distribution with a mean of 10 and a variance of 4?

<p>2 (A)</p> Signup and view all the answers

What is the purpose of data collection in statistics?

<p>To gather and measure information on variables of interest in a systematic way to answer research questions. (A)</p> Signup and view all the answers

What is the difference between an event and a sample space?

<p>An event is a subset of a sample space, while a sample space is the set of all possible outcomes. (B)</p> Signup and view all the answers

What does the term 'experiment probability' refer to?

<p>The probability of an event occurring based on the results of an experiment repeated many times. (A)</p> Signup and view all the answers

What is the standard normal distribution characterized by?

<p>A mean of 0 and a standard deviation of 1. (B)</p> Signup and view all the answers

Which of the following is NOT a characteristic of a normal distribution?

<p>Skewed distribution. (A)</p> Signup and view all the answers

What is the name of the distribution used to estimate population parameters when the sample size is small and the population variance is unknown?

<p>Student's T-Distribution (C)</p> Signup and view all the answers

What is the primary importance of the Central Limit Theorem?

<p>It demonstrates that as sample size increases, the sampling distribution of the mean approaches a normal distribution. (D)</p> Signup and view all the answers

Which of the following best describes a parameter?

<p>A measure calculated from the entire population. (B)</p> Signup and view all the answers

What is the purpose of a confidence interval?

<p>To estimate a range of plausible values for a population parameter. (C)</p> Signup and view all the answers

What is the relationship between the Central Limit Theorem and the Student's T-Distribution?

<p>The Central Limit Theorem states that as the sample size increases, the Student's T-Distribution becomes more similar to the standard normal distribution. (B)</p> Signup and view all the answers

Which of these is NOT a characteristic of the normal distribution?

<p>It is a discrete probability distribution. (D)</p> Signup and view all the answers

What is a percentile?

<p>A percentage of the population that falls below a specific score. (D)</p> Signup and view all the answers

What is a 'statistic'?

<p>A measure that describes a characteristic of a sample. (A)</p> Signup and view all the answers

What is the standard normal distribution table used for?

<p>To determine the probability of observing a specific value in a normal distribution. (A)</p> Signup and view all the answers

Who developed the t-distribution and under what alias?

<p>William Sealy Gosset, under the alias 'Student' (D)</p> Signup and view all the answers

Flashcards

Standard Normal Distribution Table

A compilation of areas from the standard normal distribution.

Population

Data set contains all members of a specified group.

Sample

Subset of a population used for analysis.

Parameter

A measure calculated using all data in the population.

Signup and view all the flashcards

Statistic

A measure calculated using data from a sample only.

Signup and view all the flashcards

Sampling Distribution

Probability distribution for a sample statistic from repeated random samples.

Signup and view all the flashcards

Normal Distribution

A bell-shaped curve where mean, mode, and median are center and peak.

Signup and view all the flashcards

Central Limit Theorem

As sample size increases, the sampling distribution approaches normality.

Signup and view all the flashcards

Confidence Interval

A range of values used to estimate a parameter's true value.

Signup and view all the flashcards

Degrees of Freedom

Maximum number of independent values that can vary in a sample.

Signup and view all the flashcards

Probability

A branch of mathematics dealing with uncertainty and event likelihood.

Signup and view all the flashcards

Variable

An observable or measurable attribute of a person, place, thing, or idea.

Signup and view all the flashcards

Data Collection

The process of gathering and measuring information systematically.

Signup and view all the flashcards

Sample Space

The set of all possible outcomes in a probability experiment.

Signup and view all the flashcards

Event

A subset of the sample space, representing specific outcomes.

Signup and view all the flashcards

Experiment Probability

Probability determined from the results of repeated experiments.

Signup and view all the flashcards

Discrete Random Variable

A variable that can take on a finite number of distinct values.

Signup and view all the flashcards

Continuous Random Variable

A variable that can assume an infinite number of values in an interval.

Signup and view all the flashcards

Study Notes

Statistics

  • Science of developing methods for planning experiments, collecting data, analyzing it, interpreting it, and drawing conclusions
  • Deals with uncertainty

Probability

  • Branch of mathematics
  • Measures likelihood of events

Variables

  • Attributes describing people, places, things, or ideas
  • Observable and measurable characteristics

Data Collection

  • Process of gathering information
  • Enables answering research questions, testing hypotheses, and evaluating outcomes
  • Systematically gathers variable data

Sample Space

  • Set of all possible outcomes

Event

  • Subset of a sample space
  • Specific collection of outcomes

Experiment Probability

  • Determined from repeated experiments

Discrete Random Variable

  • Can take a finite (countable) number of distinct values
  • Values are exact, non-negative numbers

Continuous Random Variable

  • Can assume infinite number of values within an interval

Probability Mass Function (PMF)

  • Probability distribution of a discrete random variable

Mean

  • Average of a data set
  • Calculated by adding all numbers and dividing by the count

Variance

  • Statistical measure of data spread around the mean

Standard Deviation

  • Measures dispersion of data relative to the mean
  • Calculated as the square root of variance

Normal Distribution

  • Bell-shaped curve
  • Mean, mode, and median are at the center

Standard Normal Distribution

  • Normal distribution with a mean of 0 and standard deviation of 1

Standard Normal Distribution Table

  • Compilation of areas from the standard normal distribution

Population

  • Complete set of members in a specified group

Sample

  • Subset of a population

Parameter

  • Measure or characteristic from all data values in a population

Sampling Distribution

  • Probability distribution of sample statistics obtained from repeated samples

Normal Distribution

  • Data distribution often observed
  • Characterized by a bell-shaped curve with mean, mode, and median as center

Central Limit Theorem

  • Sampling distribution of the mean approaches a normal distribution as sample size increases

Student's T-Distribution

  • Probability distribution used to estimate population parameters with small sample sizes

William Sealy Gosset

  • Developed the t-distribution
  • Published under the pseudonym "Student"

Percentile

  • Describes how a score compares to others in a set

Confidence Interval

  • Range of values used to estimate a parameter

Narrowness of Confidence Interval

  • Related to the confidence interval's width and length

Degree of Freedom

  • Maximum logically independent values varying in a sample

Studying That Suits You

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

Quiz Team

More Like This

Use Quizgecko on...
Browser
Browser