# Should I use multilevel modeling? One between-subjects continous predictor, one within-subjects categorical predictor

I have recently collected my dissertation data. I would like to know if I should use multilevel modeling to answer my research questions.

Here is a brief summary of my method:

Participants (n = 392 women) were asked to read a passage and imagine they were in the situation described. According to the passage, the participant has just moved to a new town and hopes to make some friends; to this end, the participant has plans to meet with a woman the participant believes might become a good friend someday. Participants were then asked to indicate how they would dress if they were in the situation described in the passage. Participants chose one of several outfits which varied in modesty.

Participants then read a second passage and were again told to imagine they were in the situation described. The second passage was similar to the first, but this time, according to the passage, the participant’s social media account was recently hacked to make it seem like the participant sleeps with a lot of men, and the potential female friend with whom the participant will meet has seen the hacked account. After reading the passage, the participants followed the same procedure they did after the first passage.

In my data set, I refer to the first passage as 'control' and the second passage as 'promiscuous'.

Participants then completed a religiosity scale. Religiosity was measured with 8 items using 7-point Likert scales. The mean score for these 8 items served as a measure of participant religiosity, with higher scores indicating greater religiosity.

Therefore, I have two predictors:

1. Religiosity (Between-subjects, continuous data, ranging from 1.25 to 7.00)

2. Passage (Within-subjects, categorical [control, promiscuous])

My criterion/dependent variable is Outfit Modesty (continuous data, ranging from 2.67 to 6.41).

I would like to test the main effect of Religiosity on Outfit Modesty, the main effect of Passage on Outfit Modesty, and the interaction between Religiosity and Passage.

Note that the Outfit Modesty data are not normally distributed for either passage, as you can see below:

Also, the data distribution for Religiosity seems bimodal, as you can see below:

Can I and should I use multilevel modeling?

• Can you offer more information about your data? For example, for the "Vignette (Within-subjects, categorical [2 vignettes = 2 categories])" why they are 2 categories? What are they? Also the Religiosity, what is the range? I feel the question is too vague, can you also show a few rows of your data? Nov 13, 2019 at 6:22
• Your question does not mention any treatment variable with outcomes of "control" and "promiscuous", but your histograms show these. Can you explain?
– Ben
Nov 13, 2019 at 8:40