Randomized Experiments
80 Questions
0 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

In the RAND Health Insurance Experiment (HIE), how many families were randomly assigned to different insurance coverage plans?

  • 1,000 families
  • 3,000 families
  • 2,000 families (correct)
  • 4,000 families

    • What was the duration of the STAR experiment in Tennessee?

  • Two years
  • Five years
  • Four years (correct)
  • Three years

    • What was the purpose of the modified tablet treatment group in Carter et al.'s study?

  • To restrict laptop usage
  • To examine the impact of tablet usage on academic performance (correct)
  • To evaluate study habits
  • To compare tablet and laptop performance

    • Which of the following was NOT an insurance coverage plan in the RAND Health Insurance Experiment?

    <p>80% co-payment</p> Signup and view all the answers

    What was the role of part-time teacher’s aides in the STAR experiment in Tennessee?

    <p>To work with the primary teacher in small classes</p> Signup and view all the answers

    Which experiment cost about $12 million and involved a cohort of kindergartners?

    <p>Project STAR Tennessee</p> Signup and view all the answers

    What differentiated the treatment group from the 'modified tablet' group in Carter et al.'s study?

    <p>'Modified tablet' group could only use tablets flat on desk</p> Signup and view all the answers

    What was unique about the class sizes in the STAR experiment?

    <p>'Regular classes' with part-time teacher's aides had 13-17 children</p> Signup and view all the answers

    What does the identification problem in causal analysis aim to measure?

    <p>The difference in expected outcomes between treatment and control groups</p> Signup and view all the answers

    How does random assignment help address the selection bias?

    <p>It eliminates the selection bias</p> Signup and view all the answers

    In a randomized experiment, how is the treatment assignment determined?

    <p>By a lottery</p> Signup and view all the answers

    What is the purpose of using randomization in experimental design?

    <p>To ensure that each subject has an equal chance of being assigned to treatment or control groups</p> Signup and view all the answers

    How does random assignment impact the causal inference process in experiments?

    <p>It strengthens causal inference by reducing bias</p> Signup and view all the answers

    What is the primary goal of randomization in a causal analysis?

    <p>To minimize bias in estimating causal effects</p> Signup and view all the answers

    Why is random assignment considered essential in experimental design?

    <p>To reduce the influence of confounding variables</p> Signup and view all the answers

    How does random assignment affect the interpretation of cause-and-effect relationships?

    <p>It simplifies interpretation by removing confounding factors</p> Signup and view all the answers

    What does random assignment in a randomized experiment make independent of potential outcomes?

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

    In a randomized experiment, what does the independence between potential outcomes and treatment imply?

    <p>Equal expected outcomes for each treatment group</p> Signup and view all the answers

    What does AT T represent in the context of a randomized experiment?

    <p>Difference in expected outcomes between treatment groups</p> Signup and view all the answers

    What problem does random assignment solve in experimental design?

    <p>Selection bias</p> Signup and view all the answers

    What does E[Y1i − Y0i |Di = 1] represent in a randomized experiment?

    <p>Average effect in the whole population</p> Signup and view all the answers

    In regression analysis of experiments, what is assumed to be constant?

    <p>(Y1i − Y0i)</p> Signup and view all the answers

    What is meant by AT E in the context of a randomized experiment?

    <p>$E[Y1i - Y0i]$</p> Signup and view all the answers

    How does randomization make treatment and no-treatment groups comparable in pre-treatment characteristics?

    <p>$E[Y0i|Di=0] = E[Y0i|Di=1] = E[Y0i]$</p> Signup and view all the answers

    What is a common question to ask about a randomized experiment's design?

    <p>If the treatment groups have different characteristics</p> Signup and view all the answers

    What is a key aspect to test when examining the credibility of an experimental design?

    <p>Statistical significance of differences between treatment groups</p> Signup and view all the answers

    Which characteristic of highly disciplined students contributes to the absence of compliance issues in the study?

    <p>They have better time management skills</p> Signup and view all the answers

    What impact does the ability to access electronic devices during class have on students' learning outcomes?

    <p>A combination of positive and negative effects</p> Signup and view all the answers

    In a randomized experiment, what does it mean if pre-treatment outcomes and covariates are balanced across treatment groups?

    <p>The randomization process was successful</p> Signup and view all the answers

    What aspect makes the United States Military Academy an ideal setting for a randomized trial to evaluate online teaching?

    <p>The curriculum is uniform and graded events are identical</p> Signup and view all the answers

    What did Kofoed et al. do to control for instructor effects in their experiment on online learning?

    <p>Each instructor taught half their load online and half in-person</p> Signup and view all the answers

    What is the main goal of setting up a randomized trial for evaluating online teaching at the United States Military Academy?

    <p>To assess the impact of online teaching on academic performance</p> Signup and view all the answers

    What does the regression model presented in the text help to estimate?

    <p>The treatment effect</p> Signup and view all the answers

    In the context of the classical linear regression model, what does mean independence of errors imply?

    <p>OLS estimation of the treatment effect is unbiased</p> Signup and view all the answers

    What is the role of randomization in ensuring mean independence in the classical linear regression model?

    <p>It ensures that E[ηi |Di = 1] − E[ηi |Di = 0] = 0</p> Signup and view all the answers

    Why is controlling for other covariates X not needed in the randomization setup described in the text?

    <p>Because E[ηi |Di = 1] − E[ηi |Di = 0] = 0 under randomization</p> Signup and view all the answers

    What does the selection bias in experiments amount to according to the text?

    <p>Difference between treatment and no-treatment groups</p> Signup and view all the answers

    In the context of regression analysis of experiments, what does E[Yi |Di = 1] − E[Yi |Di = 0] represent?

    <p>Treatment effect τ</p> Signup and view all the answers

    What is the main implication of the constant-effect assumption in evaluating treatment effects?

    <p><code>E[Yi |Di = 1] − E[Yi |Di = 0] = τ</code></p> Signup and view all the answers

    Based on the text, why does OLS provide unbiased estimates for the treatment effect τ?

    <p><code>E[ηi |Di = 1] − E[ηi |Di = 0] = 0</code> after randomization</p> Signup and view all the answers

    What is the importance of testing for statistically significant differences in pre-treatment outcomes and other covariates across treatment groups in a randomized experiment?

    <p>To ensure that randomization successfully balanced the subjects characteristics across treatment groups.</p> Signup and view all the answers

    Why is the United States Military Academy at West Point considered an ideal setting for a randomized trial to evaluate online teaching?

    <p>Students have little control over their academic schedules and peer networks, making random assignment feasible.</p> Signup and view all the answers

    What are the potential positive and negative effects of using electronic devices on students' learning outcomes?

    <p>Positive: ability to take notes faster. Negative: potential distractions from web-surfing.</p> Signup and view all the answers

    How did Kofoed et al. control for instructor effects in their experiment on online learning?

    <p>Each instructor taught half of their four section teaching load online and half in-person.</p> Signup and view all the answers

    What does randomized assignment in a randomized experiment ensure the independence of?

    <p>Potential outcomes from treatment assignment.</p> Signup and view all the answers

    What is the main implication of the constant-effect assumption in evaluating treatment effects?

    <p>That the treatment effect is consistent across all subjects.</p> Signup and view all the answers

    Why is random assignment considered essential in experimental design?

    <p>To ensure that treatment and no-treatment groups are comparable in pre-treatment characteristics.</p> Signup and view all the answers

    What differentiated the treatment group from the 'modified tablet' group in Carter et al.'s study on the impact of electronic devices on learning outcomes?

    <p>The 'modified tablet' group was randomly allowed to access their devices during class.</p> Signup and view all the answers

    What was the main difference between the treatment group and the 'modified tablet' group in Carter et al.'s study?

    <p>The treatment group could use laptops and tablets without restriction, while the 'modified tablet' group was only allowed to use tablets flat on the desk surface.</p> Signup and view all the answers

    What was the unique aspect of the experimental design in the RAND Health Insurance Experiment (HIE)?

    <p>The HIE randomly assigned 2,000 families from six US cities to different insurance coverage plans.</p> Signup and view all the answers

    In the STAR experiment in Tennessee, what were the three treatments that students were randomly assigned to?

    <p>Small classes with 13-17 children, regular classes with 22-25 children, and part-time teacher’s aide regular classes with full-time teacher’s aide.</p> Signup and view all the answers

    What was the main goal of the STAR experiment in Tennessee?

    <p>To estimate the effects of smaller classes in primary school.</p> Signup and view all the answers

    What differentiated the treatment group from the 'modified tablet' group in Carter et al.'s study?

    <p>The treatment group could use laptops and tablets without restriction, while the 'modified tablet' group was only allowed to use tablets flat on the desk surface.</p> Signup and view all the answers

    What was the role of the part-time teacher’s aides in the STAR experiment in Tennessee?

    <p>Part-time teacher’s aides were involved in the regular classes with full-time teacher’s aides.</p> Signup and view all the answers

    What differentiated the treatment group from the 'modified tablet' group in the study by Carter et al. (2017)?

    <p>The treatment group could use laptops and tablets without restriction, while the 'modified tablet' group was only allowed to use tablets flat on the desk surface.</p> Signup and view all the answers

    What was the main implication of the constant-effect assumption in evaluating treatment effects?

    <p>The constant-effect assumption simplifies the interpretation of treatment effects by assuming the effect is consistent across all observations.</p> Signup and view all the answers

    Explain the identification problem in causal analysis as mentioned in the text.

    <p>The identification problem aims to measure the causal effect by comparing outcomes under different treatment conditions.</p> Signup and view all the answers

    How does random assignment help address the selection bias in experiments?

    <p>Random assignment helps mitigate selection bias by ensuring that treatment and control groups are comparable on average before treatment.</p> Signup and view all the answers

    What role does randomization play in ensuring mean independence in the classical linear regression model?

    <p>Randomization ensures that treatment assignment is independent of potential outcomes, leading to mean independence in the regression model.</p> Signup and view all the answers

    How does random assignment affect the interpretation of cause-and-effect relationships in experiments?

    <p>Random assignment allows for a clearer interpretation of cause-and-effect relationships by minimizing the influence of confounding variables.</p> Signup and view all the answers

    What does random assignment in a randomized experiment make independent of potential outcomes?

    <p>Random assignment makes the treatment assignment independent of potential outcomes, ensuring a fair comparison between treatment and control groups.</p> Signup and view all the answers

    What problem does random assignment solve in experimental design?

    <p>Random assignment solves the issue of selection bias by ensuring that treatment and control groups are comparable on average before the treatment is applied.</p> Signup and view all the answers

    Explain the impact of random assignment on the causal inference process in experiments.

    <p>Random assignment strengthens causal inference by providing a more robust basis for attributing observed outcomes to the treatment.</p> Signup and view all the answers

    What aspect of highly disciplined students contributes to the absence of compliance issues in a study?

    <p>The high discipline of students contributes to compliance as they are more likely to adhere to the study protocols and treatment conditions.</p> Signup and view all the answers

    What is the implication of random assignment in terms of potential outcomes and treatment?

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

    What does AT T represent in the context of experimental design?

    <p>Average Treatment Effect</p> Signup and view all the answers

    How does random assignment solve the selection problem in experiments?

    <p>Makes treatment and no-treatment groups comparable</p> Signup and view all the answers

    What does E[Y1i - Y0i |Di = 1] represent in a randomized experiment?

    <p>Average Treatment Effect</p> Signup and view all the answers

    In the context of regression analysis of experiments, what does Y1i - Y0i = τ being constant imply?

    <p>Constant treatment effect</p> Signup and view all the answers

    What is the role of randomization in ensuring mean independence in the classical linear regression model?

    <p>Prevents correlation between treatment assignment and potential outcomes</p> Signup and view all the answers

    How does randomization impact the interpretation of cause-and-effect relationships?

    <p>Ensures causal inference</p> Signup and view all the answers

    What is the main goal of setting up a randomized trial for evaluating online teaching?

    <p>Evaluating the treatment effect</p> Signup and view all the answers

    Explain the role of randomization in ensuring mean independence in the classical linear regression model.

    <p>Randomization ensures mean independence by implying that E[ηi |Di = 1] − E[ηi |Di = 0] = 0.</p> Signup and view all the answers

    What does the selection bias in experiments amount to according to the text?

    <p>Selection bias amounts to the correlation between Di and ηi.</p> Signup and view all the answers

    How does random assignment help address the selection bias?

    <p>Random assignment helps address selection bias by making the treatment and no-treatment groups comparable in pre-treatment characteristics.</p> Signup and view all the answers

    What is the main implication of the constant-effect assumption in evaluating treatment effects?

    <p>The main implication is that under the constant-effect assumption, the treatment effect is given by τ.</p> Signup and view all the answers

    What does the identification problem in causal analysis aim to measure?

    <p>The identification problem aims to measure the treatment effect τ.</p> Signup and view all the answers

    What is the primary goal of randomization in a causal analysis?

    <p>The primary goal of randomization is to ensure that E[ηi |Di = 1] − E[ηi |Di = 0] = 0.</p> Signup and view all the answers

    What does E[Yi |Di = 1] − E[Yi |Di = 0] represent in the context of regression analysis of experiments?

    <p>E[Yi |Di = 1] − E[Yi |Di = 0] represents the treatment effect τ.</p> Signup and view all the answers

    Why is controlling for other covariates X not needed in the randomization setup described in the text?

    <p>Controlling for other covariates X is not needed because randomization ensures mean independence, making OLS unbiased for τ.</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser