Untitled Quiz

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson
Download our mobile app to listen on the go
Get App

Questions and Answers

What does a Pearson's r value of -0.9 indicate about the relationship between two variables?

  • There is a strong negative association. (correct)
  • There is a weak negative association.
  • There is no significant association.
  • There is a strong positive association.

Which statement accurately describes a null hypothesis significance test in correlation analysis?

  • It proves that correlation implies causation.
  • It supports the existence of an association if the p-value is greater than 0.05.
  • It rejects the null hypothesis if the p-value is less than 0.05. (correct)
  • It determines the exact strength of the correlation.

What is the main purpose of correlation analysis?

  • To analyze the variance within a single population.
  • To determine the cause-and-effect relationship between two variables.
  • To predict the outcome of one variable based on another.
  • To examine associations between two variables. (correct)

In which scenario would a repeated measures t-test be appropriate?

<p>Measuring IQ before and after a specific intervention in the same group. (D)</p> Signup and view all the answers

How are the correlation coefficients interpreted regarding their values?

<p>Values close to -1 or +1 indicate a stronger association. (B)</p> Signup and view all the answers

What is the null hypothesis in an independent sample t-test?

<p>There will be no significant difference between the population means. (D)</p> Signup and view all the answers

In an independent groups research design, what characterizes the participants?

<p>They are from different groups or conditions. (D)</p> Signup and view all the answers

What does a t-score indicate in the context of an independent sample t-test?

<p>The difference between two means is significant. (D)</p> Signup and view all the answers

What is the effect size in the context of an independent samples t-test?

<p>It measures the strength of the relationship between the two groups. (D)</p> Signup and view all the answers

What characterizes a repeated measures t-test?

<p>Participants' scores are compared across multiple occasions. (C)</p> Signup and view all the answers

In correlation research design, what is being assessed?

<p>The relationship between two variables. (B)</p> Signup and view all the answers

When should the null hypothesis be rejected in the context of a t-test?

<p>When the t-score is extreme for the degrees of freedom. (D)</p> Signup and view all the answers

What does a significant p-value indicate in hypothesis testing?

<p>The groups are statistically different from each other. (A)</p> Signup and view all the answers

What type of test should be used when the population standard deviation is unknown?

<p>Single sample t-test (A)</p> Signup and view all the answers

What does the t-test use as an estimate of the population standard deviation?

<p>Sample standard deviation (D)</p> Signup and view all the answers

How do you calculate degrees of freedom for a single sample t-test?

<p>One less than the sample size (A)</p> Signup and view all the answers

What is the significance level typically applied in null hypothesis significance testing?

<p>5% (D)</p> Signup and view all the answers

In the t-test, what must we consider along with the sample mean to determine its probability?

<p>Sample size and degrees of freedom (C)</p> Signup and view all the answers

Which of the following statements regarding the critical limits in t-tests is true?

<p>Critical limits vary based on sample size and degrees of freedom. (B)</p> Signup and view all the answers

What would the probability need to be for the null hypothesis to be accepted in the head injury IQ example?

<p>Greater than 5% (A)</p> Signup and view all the answers

Which of the following is a primary difference between the z-test and the t-test?

<p>Z-tests require the population standard deviation to be known. (C)</p> Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Single Sample t-test (Module 6)

  • Used when population standard deviation is unknown; estimates it using sample standard deviation.
  • Similar to z-test in process, using null hypothesis significance testing.
  • Uses t-distribution, requiring degrees of freedom (df = n-1) to determine probability of sample mean. Critical limits vary based on sample size and df.
  • Example: Assessing if head injury affects IQ. Null hypothesis: head injury has no effect.

Independent Samples t-test (Module 7)

  • Uses independent groups research design: participants assigned to different groups/conditions.
  • Assesses if the difference between two sample means is significantly different from zero.
  • JASP output provides descriptives, t-score, p-value, effect size.
  • Tests if samples originate from the same population.
  • Null hypothesis: There is no significant difference between population means.
  • A p-value less than 0.05 indicates statistical significance, rejecting the null hypothesis.

Repeated Measures t-test (Module 8)

  • Uses repeated measures research design: each participant measured multiple times (e.g., pre- and post-treatment).
  • Assesses significant difference in participant scores before and after an event or intervention.
  • Samples come from different populations (before and after).
  • Also known as paired samples or related samples t-test.
  • Example research question: Is there a change over time?

Correlation (Module 9)

  • Uses correlational research design exploring the relationship between two variables.
  • Examines linear and symmetrical associations.
  • Pearson's r measures correlation in a sample; ranges from -1 to +1.
  • Values near -1 or +1 indicate strong associations; 0 indicates no association.
  • Positive correlation: as one variable increases, the other increases. Negative correlation: as one increases, the other decreases.
  • Can infer from sample to population correlations using null hypothesis significance testing. Significant correlations suggest an association in the population.
  • Example: Association between age and IQ; testing if there is a positive correlation (smarter with age).
  • Scatterplots visually represents the correlations.

Choosing the Right t-test

  • Single Sample: Comparing a sample mean to a known population mean (population standard deviation unknown).
  • Independent Samples: Comparing means of two independent groups.
  • Repeated Measures: Comparing means of the same group at different times or under different conditions.
  • Correlational: Exploring the relationship between two continuous variables.

Studying That Suits You

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

Quiz Team

Related Documents

T Test Only PDF

More Like This

Untitled Quiz
19 questions

Untitled Quiz

WellRunHydrogen avatar
WellRunHydrogen
Untitled Quiz
18 questions

Untitled Quiz

RighteousIguana avatar
RighteousIguana
Untitled Quiz
50 questions

Untitled Quiz

JoyousSulfur avatar
JoyousSulfur
Untitled Quiz
48 questions

Untitled Quiz

StraightforwardStatueOfLiberty avatar
StraightforwardStatueOfLiberty
Use Quizgecko on...
Browser
Browser