Students in desperate need to understand !
Posted: Tue Jun 06, 2023 8:14 pm
Hi there ! I hope it's gonna be understandible, as I am a very newbie student on statistics and french speaker, my statistics questions in english might be a bit messy !
We are psych students, second year, distance education, in France. For the context.
We exchange with our teachers in writing mostly, so when they don't answer, it's a bit tricky to find answers and really comprehend the class !
We have a class named Experimental method, and we're learning experimental design, unifactorial design, multifactorial design, within subjects design and between subjects design … you know the drill !
We had an exam in April, presented a first set of data, for a factorial between subjects design (reading time with 2 conditions). The other independent variable of interest were the reading level category for every reader, 3 modalities: average, good, excellent.
For the replication of the experiment,
the instructions stated :
"The experiment presented here was replicated by another group of researchers. They also included the moment of testing as a new variable. The researchers tested the subjects in the morning at the start of class and in the evening at the end of class."
We have compared a dozen copies, some with excellent grades (around 18/19) and others a little less so (around 11/12), and the main difference is presentation in jamovi and we have a problem understanding ...
The high-scoring copies proposed a table which, in my opinion, is de facto between subjet design: in fact, a new "time of testing" column was added, with "morning/evening" as the modality (see attachment), so the number of participants is necessarily doubled. Jamovi does not take into account any ID column, and considers that two IDs, even identical ones, on two different lines are two distinct individuals. No ?
On the other hand, the lower-scoring copies proposed an within subjects design (making the experiment a mixed design): the same students were tested in the morning and evening. Compared with the first three questions, there is now a Morning Reading Time column and an Evening Reading Time column (see attachment).
Two possible explanations have been considered, but the teacher is not responding. We are loosing our minds, trying to understand...
1 / If he considered this to be an inter design :
How could we know that the students tested in the evening were not the same students as in the morning? The statement preceding questions 4 and 5 was as follows:
"The experiment presented here was replicated by another group of researchers. They also included the time of the test as a new variable. The researchers tested subjects in the morning at the beginning of class and in the evening at the end of class."
Reading this instruction, it seems obvious to us that the same subjects were tested in the morning and in the evening, but in the end the sentence is entirely open to interpretation. But if an interpretation was possible, shouldn't both solutions have been encouraged, especially when justified in the student's copy? This doesn't seem to be apparent from your correction and the grades he gave...
2 / He considered this to be an intra design
If so, we have the feeling that he accepted the version with one column "time of passing" and not the version with the two columns "Morning reading time" / "Evening reading time", which leaves us a little perplexed...
Perhaps we're using Jamovi in the wrong way, as mentioned in our last class, last year, each line corresponds to a different individual.
Why would he duplicates lines ?
No matter how many times we've tried using an ID column containing complex, identical numbers to try and "reproduce" an individual, Jamovi always considers them as different individuals. By presenting an intra design in this way, there would be a problem in making comparisons of averages, for example...
If anyone as a clear explanation to this, we will be glad to ear it !
Thank you
We are psych students, second year, distance education, in France. For the context.
We exchange with our teachers in writing mostly, so when they don't answer, it's a bit tricky to find answers and really comprehend the class !
We have a class named Experimental method, and we're learning experimental design, unifactorial design, multifactorial design, within subjects design and between subjects design … you know the drill !
We had an exam in April, presented a first set of data, for a factorial between subjects design (reading time with 2 conditions). The other independent variable of interest were the reading level category for every reader, 3 modalities: average, good, excellent.
For the replication of the experiment,
the instructions stated :
"The experiment presented here was replicated by another group of researchers. They also included the moment of testing as a new variable. The researchers tested the subjects in the morning at the start of class and in the evening at the end of class."
We have compared a dozen copies, some with excellent grades (around 18/19) and others a little less so (around 11/12), and the main difference is presentation in jamovi and we have a problem understanding ...
The high-scoring copies proposed a table which, in my opinion, is de facto between subjet design: in fact, a new "time of testing" column was added, with "morning/evening" as the modality (see attachment), so the number of participants is necessarily doubled. Jamovi does not take into account any ID column, and considers that two IDs, even identical ones, on two different lines are two distinct individuals. No ?
On the other hand, the lower-scoring copies proposed an within subjects design (making the experiment a mixed design): the same students were tested in the morning and evening. Compared with the first three questions, there is now a Morning Reading Time column and an Evening Reading Time column (see attachment).
Two possible explanations have been considered, but the teacher is not responding. We are loosing our minds, trying to understand...
1 / If he considered this to be an inter design :
How could we know that the students tested in the evening were not the same students as in the morning? The statement preceding questions 4 and 5 was as follows:
"The experiment presented here was replicated by another group of researchers. They also included the time of the test as a new variable. The researchers tested subjects in the morning at the beginning of class and in the evening at the end of class."
Reading this instruction, it seems obvious to us that the same subjects were tested in the morning and in the evening, but in the end the sentence is entirely open to interpretation. But if an interpretation was possible, shouldn't both solutions have been encouraged, especially when justified in the student's copy? This doesn't seem to be apparent from your correction and the grades he gave...
2 / He considered this to be an intra design
If so, we have the feeling that he accepted the version with one column "time of passing" and not the version with the two columns "Morning reading time" / "Evening reading time", which leaves us a little perplexed...
Perhaps we're using Jamovi in the wrong way, as mentioned in our last class, last year, each line corresponds to a different individual.
Why would he duplicates lines ?
No matter how many times we've tried using an ID column containing complex, identical numbers to try and "reproduce" an individual, Jamovi always considers them as different individuals. By presenting an intra design in this way, there would be a problem in making comparisons of averages, for example...
If anyone as a clear explanation to this, we will be glad to ear it !
Thank you