Note. Data for this study was collected by the Wyoming Community College Commission (WCCC) from 2012 to 2023, encompassing 5448 students who enrolled in CCC. Several criteria were applied to create the analytic sample. Only students’ first CCC attempt was included, concurrent enrollment sections taught in high schools, all dual enrollment CCC students, students with HS GPA which was larger than 4.0, and students with missing data were listwise deleted. The analysis focused on CCC sections from the 2013-2014 academic year onward, allowing summer 2012 through summer 2014 to serve as a lookback period for capturing students’ precalculus coursework history. Sections with fewer than three students were removed to allow for adequate sample sizes for multilevel modeling (Clarke, 2008). The final analytic sample consisted of 745 students in 91 course sections across 5 of Wyoming’s 7 CCs. The smallest section size was 3, and the largest was 22 students.
Level 1 (student) intercept is represented by the \(1_{1}\) triangle on the left, with level 1 predictors below in rectangles; Level 2 predictors are arranged horizontally along the top in rectangles with the level 2 intercept represented with the \(1_{2}\) triangle. Cross-level interaction term edges and their coefficient labels are color coded with their β-nodes. The intercept varies randomly across sections, indicated by the random effect \(u_{0j}\). Variables in bold font are centered within section (cwc), variables bold-italic font are grand mean centered (gmc). Parameter estimates without parentheses are significant (p≤0.05) and within parentheses are non-significant (p>0.05).
The model can be written in hierarchical form with the student \(\beta\) level coefficients, which are then written in terms of section \(\gamma\) level coefficients. The random effect for the intercept is \(u_{0j}\) and there are no random slopes. There are two student-level interaction terms and two cross-level interaction terms.
Level 1 Model:
\[ \begin{aligned} \log\left(\frac{P(Y_{ij} = \text{Pass})}{P(Y_{ij} = \text{Fail})}\right) &= \beta_{0j}+\beta_{1j} (\text{HSPGA})_{cwc}+\beta_{2j} (\text{max actmath})_{cwc} \\ &\quad + \beta_{3j} (\text{years calc since HS})_{cwc} + \beta_{4j} (\text{math courses below 2200})_{cwc} \\ &\quad + \beta_{5j} (\text{female})+\beta_{6j} (\text{concurrent prereq})_{cwc} + \beta_{7j} (\text{URM}) \\ &\quad + \beta_{8j} (\text{HSGPA})_{cwc}×(\text{years calc since HS})_{cwc} \\ &\quad +\beta_{9j} (\text{concurrent prereq})_{cwc} ×(\text{max actmath})_{cwc} \end{aligned} \]
Level 2 Model:
\[ \begin{aligned} &\quad \beta_{0j} = γ_{00} + \gamma_{01} (\text{HSGPA})_{gmc}+\gamma_{02} (\text{coreqcollege}) +u_{0j} \\ &\quad \beta_{1j} =\gamma_{10} \\ &\quad \beta_{2j} =\gamma_{20} \\ &\quad \beta_{3j} =\gamma_{30} \\ &\quad \beta_{4j} =\gamma_{40}+\gamma_{41} (\text{coreq college}) \\ &\quad \beta_{5j}=\gamma_{50} \\ &\quad \beta_{6j}=\gamma_{60} \\ &\quad \beta_{7j}=\gamma_{70}+\gamma_{71} (\text{HSGPA})_{gmc}\\ &\quad \beta_{8j}=\gamma_{80} \\ &\quad \beta_{9j}=\gamma_{90} \end{aligned} \]
Substituting the section-level \(\beta\) coefficient equations into the student-level equation results in a representation of the model in combined form:
\[\begin{aligned} \log\left(\frac{P(Y_{ij} = \text{Pass})}{P(Y_{ij} = \text{Fail})}\right) &= \gamma_{00} + \gamma_{01}(\text{HSGPA})_{gmc} + \gamma_{02}(\text{CoreqCollege}) \\ &\quad + \gamma_{10}(\text{HSGPA})_{cwc} + \gamma_{20}(\text{ACTMath})_{cwc} + \gamma_{30}(\text{YearsCalc})_{cwc} \\ &\quad + \gamma_{40}(\text{MathCourses})_{cwc} + \gamma_{41}(\text{MathCourses})_{cwc} \times (\text{CoreqCollege}) \\ &\quad + \gamma_{50}(\text{Female}) + \gamma_{60}(\text{ConcurrentPrereq})_{cwc} + \gamma_{70}(\text{URM}) \\ &\quad + \gamma_{71}(\text{URM}) \times (\text{HSGPA})_{gmc} + \gamma_{80}(\text{HSGPA})_{cwc} \times (\text{YearsCalc})_{cwc} \\ &\quad + \gamma_{90}(\text{ConcurrentPrereq})_{cwc} \times (\text{ACTMath})_{cwc} + u_{0j} \end{aligned}\]
| Component | Description |
|---|---|
| Level 1 Structure | \(\log\left(\frac{P(Pass)}{P(Fail)}\right) = \beta_{0j} + \sum\beta_{qj}X_{qij}\) |
| Level 2 Structure | \(\beta_{qj}=\gamma_{q0}+\sum\gamma_{qs}W_{sj}+u_{qj}\) |
| Level 1 Predictors | HSGPA, ACT Math, Years since HS, Math Courses, Female, Concurrent Prereq, URM |
| Level 2 Predictors | HSGPA (gmc), Coreq College |
| Level 1 Interactions | HSGPA×Years, Concurrent×ACTMath |
| Cross Level Interactions | Math Courses×Coreq, URM×HSGPA(gmc) |
| Random Effect | \(u_{0j} \sim N(0, \tau_{00}^2)\) |
| Effect | Parameter | Level | Centering |
|---|---|---|---|
| Intercept | \(\gamma_{00}\) | – | – |
| HSGPA (gmc) | \(\gamma_{01}\) | Section | Grand-Mean |
| Coreq College | \(\gamma_{02}\) | Section | None |
| HSGPA (cwc) | \(\gamma_{10}\) | Student | Section-Mean |
| ACT Math (cwc) | \(\gamma_{20}\) | Student | Section-Mean |
| Years since HS (cwc) | \(\gamma_{30}\) | Student | Section-Mean |
| Math Courses (cwc) | \(\gamma_{40}\) | Student | Section-Mean |
| Female | \(\gamma_{50}\) | Student | None |
| Concurrent Prereq (cwc) | \(\gamma_{60}\) | Student | Section-Mean |
| URM | \(\gamma_{70}\) | Student | None |
| Interaction | Parameter | Level |
|---|---|---|
| Math Courses (cwc) × Coreq College | \(\gamma_{41}\) | Cross-Level |
| URM × HSGPA (gmc) | \(\gamma_{71}\) | Cross-Level |
| HSGPA (cwc) × Years since HS (cwc) | \(\gamma_{80}\) | Student-Level |
| Concurrent Prereq (cwc) × ACT Math (cwc) | \(\gamma_{90}\) | Student-level |
| Variable | N | M | SD | Min | Max |
|---|---|---|---|---|---|
| HS.GPA | 745 | 3.49 | 0.44 | 1.80 | 4.00 |
| ACT.Math | 745 | 24.10 | 3.57 | 13.00 | 34.00 |
| Years.since.HS | 745 | 1.26 | 1.28 | 0.21 | 8.21 |
| Math.prereqs | 745 | 1.44 | 1.16 | 0.00 | 7.00 |
| Variable | Yes | No | Percent_Yes | Percent_No |
|---|---|---|---|---|
| Female | 288 | 457 | 38.7 | 61.3 |
| URM | 139 | 606 | 18.7 | 81.3 |
| Concurrent prereq | 148 | 597 | 19.9 | 80.1 |
| Coreq college | 278 | 467 | 37.3 | 62.7 |
| Pass | 537 | 208 | 72.1 | 27.9 |
| Statistic | Value |
|---|---|
| Total Sections | 91.0 |
| Total Students | 745.0 |
| Mean Section Size | 8.2 |
| SD Section Size | 4.6 |
| Min Section Size | 3.0 |
| Max Section Size | 22.0 |
| Variable | M | SD | Min | Max |
|---|---|---|---|---|
| Mean HS GPA | 3.460 | 0.210 | 2.84 | 3.94 |
| Mean ACT Math | 24.060 | 1.860 | 18.00 | 27.80 |
| Mean Years Since HS | 1.410 | 0.840 | 0.21 | 4.75 |
| Mean Math Prerequisites | 1.440 | 0.620 | 0.00 | 3.00 |
| Prop. Concurrent Prereq | 0.178 | 0.253 | 0.00 | 1.00 |
Level 1 (student) intercept is represented by the \(1_{1}\) triangle on the left, with level 1 predictors below in rectangles; Level 2 predictors are arranged horizontally along the top in rectangles with the level 2 intercept represented with the \(1_{2}\) triangle. Cross-level interaction term edges and their coefficient labels are color coded with their β-nodes. The intercept varies randomly across sections, indicated by the random effect \(u_{0j}\). Variables in bold font are centered within section (cwc), variables bold-italic font are grand mean centered (gmc). Parameter estimates without parentheses are significant (p≤0.05) and within parentheses are non-significant (p>0.05). There were three main effects and four interactions that were significant in the model. Shaded ribbon around predicted probability represents a 95% confidence interval. Horizontal axis spans range of data for variable.
The main effect of HSGPA (gmc) was significant in the model. This represents the influence of mean course-section HSGPA compared to grand mean HSGPA.
The student-level main effect of HSGPA (cwc) was significant in the model. This represents the influence of the difference between a student’s HSGPA and their course-section mean.
The main effect of math prereqs (cwc) was significant in the model. This represents the influence of the difference between the number of prerequisite math courses a student took and their course section mean.
The student-level interactionconcurrent prereq (cwc) x ACT Math (cwc) was significant in the model. Slider bar goes two standard deviations on each side of the mean of ACT Math (cwc).
The student-level interaction HSGPA (cwc) x years since HS (cwc) was significant in the model. Slider bar goes two standard deviations on each side of the mean of HSGPA (cwc).
The the cross-level interaction coreq college x math prereqs (cwc) was significant. Button toggles coreq college status.
The the cross-level interaction URM x HSGPA (gmc) was significant. Button toggles URM status.
Testing assumptions for multilevel logistic regression: multicollinearity, the log odds of the dependent variable needs to be linearly related to the independent variables, and sample sizes must be sufficient to have a minimum number of cases in each outcome.
| Component | ICC |
|---|---|
| ICC_adjusted | 0.114 |
| ICC_conditional | 0.114 |
| ICC_unadjusted | 0.114 |
| Effect | Group | Term | Estimate | SE | z | p |
|---|---|---|---|---|---|---|
| Fixed Effects | ||||||
| fixed | NA | (Intercept) | 1.017 | 0.115 | 8.823 | < 0.001 |
| Random Effects | ||||||
| ran_pars | Location_Term_Institution | sd__(Intercept) | 0.650 | NA | NA | |
| Term | Estimate | SE | z | p |
|---|---|---|---|---|
| (Intercept) | 1.174 | 0.177 | 6.613 | < 0.001 |
| HSGPA_cwc | 1.608 | 0.255 | 6.302 | < 0.001 |
| years_calc_since_HS_cwc | -0.054 | 0.093 | -0.585 | 0.559 |
| HSGPA_gmc | 2.912 | 0.642 | 4.537 | < 0.001 |
| URM | -0.215 | 0.236 | -0.911 | 0.362 |
| coreqcollege | -0.189 | 0.240 | -0.789 | 0.43 |
| math_courses_below_2200_cwc | 0.305 | 0.136 | 2.237 | < 0.05 |
| concurrent_prereq_cwc | -0.474 | 0.314 | -1.508 | 0.131 |
| max_actmath_cwc | 0.053 | 0.035 | 1.524 | 0.128 |
| female | -0.003 | 0.203 | -0.014 | 0.989 |
| HSGPA_cwc:years_calc_since_HS_cwc | -0.798 | 0.226 | -3.526 | < 0.001 |
| HSGPA_gmc:URM | -2.738 | 1.200 | -2.281 | < 0.05 |
| coreqcollege:math_courses_below_2200_cwc | -0.552 | 0.189 | -2.922 | < 0.01 |
| concurrent_prereq_cwc:max_actmath_cwc | 0.203 | 0.100 | 2.035 | < 0.05 |
| Model | npar | AIC | BIC | logLik | deviance | Chisq | df | Pr..Chisq. |
|---|---|---|---|---|---|---|---|---|
| Null Model | 2 | 873.61 | 882.83 | -434.8 | 869.61 | NA | NA | NA |
| Full Model | 15 | 802.80 | 872.00 | -386.4 | 772.80 | 96.81 | 13 | < 0.001 |
| Variable | VIF |
|---|---|
| HSGPA_cwc | 1.209 |
| years_calc_since_HS_cwc | 1.270 |
| HSGPA_gmc | 1.227 |
| URM | 1.081 |
| coreqcollege | 1.052 |
| math_courses_below_2200_cwc | 2.284 |
| concurrent_prereq_cwc | 1.126 |
| max_actmath_cwc | 1.499 |
| female | 1.100 |
| HSGPA_cwc:years_calc_since_HS_cwc | 1.179 |
| HSGPA_gmc:URM | 1.249 |
| coreqcollege:math_courses_below_2200_cwc | 1.671 |
| concurrent_prereq_cwc:max_actmath_cwc | 1.061 |