There are 5 situations below. Can someone please match the situations up with the threat. These would be in a quasi-experimental design. The threats are history, maturation, mortality, testing, and instrumentation threat. THANK YOU!
A.Kindergarten students who were identified as having difficulty staying on-task were placed in a special class to avoid disrupting their more attentive peers. The special class included an intervention to improve attention span. After 6 months, students in the special class were performing no differently on measures of attention than their peers.
B.The local university starts a freshman orientation program to reduce binge-drinking. During their first semester, the campus police also begin ticketing and fining under-age students who are caught intoxicated while on campus.
C.A literacy intervention for adolescents is implemented in a local school district. The effectiveness of the program is assessed using a oral reading fluency test, which is administered by each student's homeroom teacher.
D.An intervention intended to improve performance on the state graduation test began with 150 participants who had failed the exam on the first try. Only 75 finished. The 75 finishers performed better on their second try on the exam.
E.The state correctional institution implements a Web-based counseling program for inmates with substance abuse problems. To measure whether the program is effective, the Adult Substance Use Survey is administered to the inmates on a bi-weekly basis. Over time, the inmates show a significant decrease in their survey scores.
What are your guesses?
Here is a good site that explains the threats:
(PDF file to download):
webs.wofford.edu/reidak/Psych%20200/Threats%20to%20internal%20validity.pdf -
Sra
To match the situations with the threats in a quasi-experimental design, we need to analyze each situation and identify the potential threats. Here is a breakdown:
A. Threat: Maturation
Explanation: Maturation refers to changes that can naturally occur over time and affect the participants' behavior. In this situation, the special class included an intervention to improve attention span, which could have affected the students' performance. However, if the students in the special class were performing no differently than their peers after 6 months, it suggests that maturation might be a threat as both groups showed similar improvements.
B. Threat: History
Explanation: History refers to external factors or events that can occur during an experiment and affect the participants' behavior. In this situation, the university's orientation program and the campus police ticketing and fining under-age students could have influenced the students' drinking behavior. Therefore, history is a potential threat as these external factors might have impacted the outcome.
C. Threat: Instrumentation
Explanation: Instrumentation refers to changes in the measurement or assessment tools used in an experiment, which can affect the participants' responses. In this situation, the intervention program's effectiveness is assessed using an oral reading fluency test, which is administered by the homeroom teacher. If the teachers' administration of the test changes over time (becomes more or less lenient, for example), it could affect the results and introduce an instrumentation threat.
D. Threat: Mortality
Explanation: Mortality refers to participants dropping out or being lost from an experiment, which can affect the representativeness and validity of the results. In this situation, out of the initial 150 participants who failed the state graduation test, only 75 finished the intervention and performed better on their second try. The dropout of 75 participants could introduce a mortality threat as those who dropped out might have had different characteristics or responses that could influence the outcome.
E. Threat: Testing
Explanation: Testing refers to the effect of being tested on the participants' subsequent performance. In this situation, the inmates are administered the Adult Substance Use Survey on a bi-weekly basis before and after the implementation of the web-based counseling program. The repeated testing itself, irrespective of the intervention, could affect the inmates' responses and introduce a testing threat.
So, based on the above discussions, here are the matched situations with the threats in a quasi-experimental design:
A. Situation: Maturation Threat
B. Situation: History Threat
C. Situation: Instrumentation Threat
D. Situation: Mortality Threat
E. Situation: Testing Threat