Machine Learning - Lab 1 Independent Assignment
[Enter your name]
September 12, 2023
The lab provides space to work with data and to reflect on how the concepts and techniques introduced in each lab might apply to your own research.
To earn a badge for each lab, you are required to respond to a set of prompts for two parts:
In Part I, you will extend our model by adding another variable.
In Part II, you will reflect on your understanding of key concepts and begin to think about potential next steps for your own study.
Part I: Extending our model
In this part of the badge activity, please add another variable – a variable for the number of days before the start of the module students registered. This variable will be a third predictor. By adding it, you’ll be able to examine how much more accurate your model is (if at al, as this variable might not have great predictive power). Note that this variable is a number and so no pre-processing is necessary.
In doing so, please move all of your code needed to run the analysis over from your case study file here. This is essential for your analysis to be reproducible. You may wish to break your code into multiple chunks based on the overall purpose of the code in the chunk (e.g., loading packages and data, wrangling data, and each of the machine learning steps).
library(tidymodels)## ── Attaching packages ────────────────────────────────────── tidymodels 1.1.1 ──## ✔ broom 1.0.5 ✔ recipes 1.0.8
## ✔ dials 1.2.0 ✔ rsample 1.2.0
## ✔ dplyr 1.1.3 ✔ tibble 3.2.1
## ✔ ggplot2 3.4.3 ✔ tidyr 1.3.0
## ✔ infer 1.0.4 ✔ tune 1.1.2
## ✔ modeldata 1.2.0 ✔ workflows 1.1.3
## ✔ parsnip 1.1.1 ✔ workflowsets 1.0.1
## ✔ purrr 1.0.2 ✔ yardstick 1.2.0## ── Conflicts ───────────────────────────────────────── tidymodels_conflicts() ──
## ✖ purrr::discard() masks scales::discard()
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag() masks stats::lag()
## ✖ recipes::step() masks stats::step()
## • Search for functions across packages at https://www.tidymodels.org/find/library(tidyverse)## ── Attaching core tidyverse packages ──────────────────────── tidyverse 2.0.0 ──
## ✔ forcats 1.0.0 ✔ readr 2.1.4
## ✔ lubridate 1.9.2 ✔ stringr 1.5.0
## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ readr::col_factor() masks scales::col_factor()
## ✖ purrr::discard() masks scales::discard()
## ✖ dplyr::filter() masks stats::filter()
## ✖ stringr::fixed() masks recipes::fixed()
## ✖ dplyr::lag() masks stats::lag()
## ✖ readr::spec() masks yardstick::spec()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errorsoptions(warn.conflicts = FALSE)
library(tidymodels)
library(janitor)##
## Attaching package: 'janitor'
##
## The following objects are masked from 'package:stats':
##
## chisq.test, fisher.teststudents <- read_csv("oulad-students.csv")## Rows: 32593 Columns: 15
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (9): code_module, code_presentation, gender, region, highest_education, ...
## dbl (6): id_student, num_of_prev_attempts, studied_credits, module_presentat...
##
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.glimpse(students)## Rows: 32,593
## Columns: 15
## $ code_module <chr> "AAA", "AAA", "AAA", "AAA", "AAA", "AAA", "…
## $ code_presentation <chr> "2013J", "2013J", "2013J", "2013J", "2013J"…
## $ id_student <dbl> 11391, 28400, 30268, 31604, 32885, 38053, 4…
## $ gender <chr> "M", "F", "F", "F", "F", "M", "M", "F", "F"…
## $ region <chr> "East Anglian Region", "Scotland", "North W…
## $ highest_education <chr> "HE Qualification", "HE Qualification", "A …
## $ imd_band <chr> "90-100%", "20-30%", "30-40%", "50-60%", "5…
## $ age_band <chr> "55<=", "35-55", "35-55", "35-55", "0-35", …
## $ num_of_prev_attempts <dbl> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0…
## $ studied_credits <dbl> 240, 60, 60, 60, 60, 60, 60, 120, 90, 60, 6…
## $ disability <chr> "N", "N", "Y", "N", "N", "N", "N", "N", "N"…
## $ final_result <chr> "Pass", "Pass", "Withdrawn", "Pass", "Pass"…
## $ module_presentation_length <dbl> 268, 268, 268, 268, 268, 268, 268, 268, 268…
## $ date_registration <dbl> -159, -53, -92, -52, -176, -110, -67, -29, …
## $ date_unregistration <dbl> NA, NA, 12, NA, NA, NA, NA, NA, NA, NA, NA,…students <- students %>%
mutate(pass = ifelse(final_result == "Pass", 1, 0)) %>% # creates a new variable named "pass" and a dummy code of 1 if value of final_result equals "pass" and 0 if not
mutate(pass = as.factor(pass)) # makes the variable a factor, helping later stepsstudents <- students %>%
mutate(disability = as.factor(disability))view(students)#view(students)students %>%
count(id_student) # this many students## # A tibble: 28,785 × 2
## id_student n
## <dbl> <int>
## 1 3733 1
## 2 6516 1
## 3 8462 2
## 4 11391 1
## 5 23629 1
## 6 23632 1
## 7 23698 1
## 8 23798 1
## 9 24186 1
## 10 24213 2
## # ℹ 28,775 more rowsstudents %>%
count(code_module, code_presentation) # this many offerings## # A tibble: 22 × 3
## code_module code_presentation n
## <chr> <chr> <int>
## 1 AAA 2013J 383
## 2 AAA 2014J 365
## 3 BBB 2013B 1767
## 4 BBB 2013J 2237
## 5 BBB 2014B 1613
## 6 BBB 2014J 2292
## 7 CCC 2014B 1936
## 8 CCC 2014J 2498
## 9 DDD 2013B 1303
## 10 DDD 2013J 1938
## # ℹ 12 more rowsstudents <- students %>%
mutate(imd_band = factor(imd_band, levels = c("0-10%",
"10-20%",
"20-30%",
"30-40%",
"40-50%",
"50-60%",
"60-70%",
"70-80%",
"80-90%",
"90-100%"))) %>% # this creates a factor with ordered levels
mutate(imd_band = as.integer(imd_band)) # this changes the levels into integers based on the order of the factor levels
students## # A tibble: 32,593 × 16
## code_module code_presentation id_student gender region highest_education
## <chr> <chr> <dbl> <chr> <chr> <chr>
## 1 AAA 2013J 11391 M East Angli… HE Qualification
## 2 AAA 2013J 28400 F Scotland HE Qualification
## 3 AAA 2013J 30268 F North West… A Level or Equiv…
## 4 AAA 2013J 31604 F South East… A Level or Equiv…
## 5 AAA 2013J 32885 F West Midla… Lower Than A Lev…
## 6 AAA 2013J 38053 M Wales A Level or Equiv…
## 7 AAA 2013J 45462 M Scotland HE Qualification
## 8 AAA 2013J 45642 F North West… A Level or Equiv…
## 9 AAA 2013J 52130 F East Angli… A Level or Equiv…
## 10 AAA 2013J 53025 M North Regi… Post Graduate Qu…
## # ℹ 32,583 more rows
## # ℹ 10 more variables: imd_band <int>, age_band <chr>,
## # num_of_prev_attempts <dbl>, studied_credits <dbl>, disability <fct>,
## # final_result <chr>, module_presentation_length <dbl>,
## # date_registration <dbl>, date_unregistration <dbl>, pass <fct>set.seed(20230712)
train_test_split <- initial_split(students, prop = .80)
data_train <- training(train_test_split)
data_test <- testing(train_test_split)data_train## # A tibble: 26,074 × 16
## code_module code_presentation id_student gender region highest_education
## <chr> <chr> <dbl> <chr> <chr> <chr>
## 1 FFF 2014B 595186 M South Regi… Lower Than A Lev…
## 2 BBB 2014J 504066 F East Midla… Lower Than A Lev…
## 3 BBB 2013J 585790 F South East… HE Qualification
## 4 CCC 2014J 278413 M London Reg… HE Qualification
## 5 GGG 2014B 634933 F South Regi… Lower Than A Lev…
## 6 CCC 2014J 608577 M North Regi… HE Qualification
## 7 BBB 2014B 612120 F East Midla… Lower Than A Lev…
## 8 FFF 2013J 530852 M Wales Lower Than A Lev…
## 9 CCC 2014J 2555596 M South Regi… A Level or Equiv…
## 10 DDD 2013B 556575 M North Regi… HE Qualification
## # ℹ 26,064 more rows
## # ℹ 10 more variables: imd_band <int>, age_band <chr>,
## # num_of_prev_attempts <dbl>, studied_credits <dbl>, disability <fct>,
## # final_result <chr>, module_presentation_length <dbl>,
## # date_registration <dbl>, date_unregistration <dbl>, pass <fct>data_test## # A tibble: 6,519 × 16
## code_module code_presentation id_student gender region highest_education
## <chr> <chr> <dbl> <chr> <chr> <chr>
## 1 AAA 2013J 28400 F Scotland HE Qualification
## 2 AAA 2013J 31604 F South East… A Level or Equiv…
## 3 AAA 2013J 45462 M Scotland HE Qualification
## 4 AAA 2013J 53025 M North Regi… Post Graduate Qu…
## 5 AAA 2013J 65002 F East Angli… A Level or Equiv…
## 6 AAA 2013J 71361 M Ireland HE Qualification
## 7 AAA 2013J 77367 M East Midla… A Level or Equiv…
## 8 AAA 2013J 98094 M Wales Lower Than A Lev…
## 9 AAA 2013J 111717 F East Angli… HE Qualification
## 10 AAA 2013J 114017 F North Regi… Post Graduate Qu…
## # ℹ 6,509 more rows
## # ℹ 10 more variables: imd_band <int>, age_band <chr>,
## # num_of_prev_attempts <dbl>, studied_credits <dbl>, disability <fct>,
## # final_result <chr>, module_presentation_length <dbl>,
## # date_registration <dbl>, date_unregistration <dbl>, pass <fct>my_rec <- recipe(pass ~ disability + imd_band, data = data_train)
my_rec## ## ── Recipe ──────────────────────────────────────────────────────────────────────## ## ── Inputs## Number of variables by role## outcome: 1
## predictor: 2# specify model
my_mod <-
logistic_reg()my_mod <-
logistic_reg() %>%
set_engine("glm") %>% # generalized linear model
set_mode("classification") # since we are predicting a dichotomous outcome, specify classification; for a number, specify regression
my_mod## Logistic Regression Model Specification (classification)
##
## Computational engine: glmmy_wf <-
workflow() %>% # create a workflow
add_model(my_mod) %>% # add the model we wrote above
add_recipe(my_rec) # add our recipe we wrote abovefitted_model <- fit(my_wf, data = data_train)fitted_model## ══ Workflow [trained] ══════════════════════════════════════════════════════════
## Preprocessor: Recipe
## Model: logistic_reg()
##
## ── Preprocessor ────────────────────────────────────────────────────────────────
## 0 Recipe Steps
##
## ── Model ───────────────────────────────────────────────────────────────────────
##
## Call: stats::glm(formula = ..y ~ ., family = stats::binomial, data = data)
##
## Coefficients:
## (Intercept) disabilityY imd_band
## -0.78655 -0.28186 0.05974
##
## Degrees of Freedom: 22406 Total (i.e. Null); 22404 Residual
## (3667 observations deleted due to missingness)
## Null Deviance: 29830
## Residual Deviance: 29650 AIC: 29660final_fit <- last_fit(fitted_model, train_test_split)final_fit## # Resampling results
## # Manual resampling
## # A tibble: 1 × 6
## splits id .metrics .notes .predictions .workflow
## <list> <chr> <list> <list> <list> <list>
## 1 <split [26074/6519]> train/test spl… <tibble> <tibble> <tibble> <workflow># Collect test split predictions
final_fit %>%
collect_predictions()## # A tibble: 6,519 × 7
## id .pred_0 .pred_1 .row .pred_class pass .config
## <chr> <dbl> <dbl> <int> <fct> <fct> <chr>
## 1 train/test split 0.647 0.353 2 0 1 Preprocessor1_Model1
## 2 train/test split 0.605 0.395 4 0 1 Preprocessor1_Model1
## 3 train/test split 0.634 0.366 7 0 1 Preprocessor1_Model1
## 4 train/test split NA NA 10 <NA> 1 Preprocessor1_Model1
## 5 train/test split 0.577 0.423 16 0 0 Preprocessor1_Model1
## 6 train/test split NA NA 18 <NA> 1 Preprocessor1_Model1
## 7 train/test split 0.634 0.366 21 0 1 Preprocessor1_Model1
## 8 train/test split 0.577 0.423 24 0 1 Preprocessor1_Model1
## 9 train/test split 0.547 0.453 33 0 1 Preprocessor1_Model1
## 10 train/test split NA NA 35 <NA> 1 Preprocessor1_Model1
## # ℹ 6,509 more rowsfinal_fit %>%
collect_predictions() %>% # see test set predictions
select(.pred_class, pass) %>% # just to make the output easier to view
mutate(correct = .pred_class == pass) # create a new variable, correct, telling us when the model was and was not correct## # A tibble: 6,519 × 3
## .pred_class pass correct
## <fct> <fct> <lgl>
## 1 0 1 FALSE
## 2 0 1 FALSE
## 3 0 1 FALSE
## 4 <NA> 1 NA
## 5 0 0 TRUE
## 6 <NA> 1 NA
## 7 0 1 FALSE
## 8 0 1 FALSE
## 9 0 1 FALSE
## 10 <NA> 1 NA
## # ℹ 6,509 more rowsfinal_fit %>%
collect_predictions() %>% # see test set predictions
select(.pred_class, pass) %>% # just to make the output easier to view
mutate(correct = .pred_class == pass) %>% # create a new variable, correct, telling us when the model was and was not correct
tabyl(correct)## correct n percent valid_percent
## FALSE 2071 0.3176868 0.372549
## TRUE 3488 0.5350514 0.627451
## NA 960 0.1472618 NAstudents %>%
count(pass)## # A tibble: 2 × 2
## pass n
## <fct> <int>
## 1 0 20232
## 2 1 12361students %>%
mutate(prediction = sample(c(0, 1), nrow(students), replace = TRUE)) %>%
mutate(correct = if_else(prediction == 1 & pass == 1 |
prediction == 0 & pass == 0, 1, 0)) %>%
tabyl(correct)## correct n percent
## 0 16328 0.5009665
## 1 16265 0.4990335Previous results:
New results:
How does the accuracy of this new model compare? Add a few reflections below:
Part II: Reflect and Plan
Part A: Please refer back to Breiman’s (2001) article for these three questions.
- Can you summarize the primary difference between the two cultures of statistical modeling that Breiman outlines in his paper?
- How has the advent of big data and machine learning affected or reinforced Breiman’s argument since the article was published?
- Breiman emphasized the importance of predictive accuracy over understanding why a method works. To what extent do you agree or disagree with this stance?
Part B:
- How good was the machine learning model you developed in the badge activity? What if you read about someone using such a model as a reviewer of research? Please add your thoughts and reflections following the bullet point below.
- How might the model be improved? Share any ideas you have at this time below:
Part C: Use the institutional library (e.g. NU Library), Google Scholar or search engine to locate a research article, presentation, or resource that applies machine learning to an educational context aligned with your research interests. More specifically, locate a machine learning study that involves making predictions.
Provide an APA citation for your selected study.
What research questions were the authors of this study trying to address and why did they consider these questions important?
What were the results of these analyses?
Knit and Publish
Complete the following steps to knit and publish your work:
First, change the name of the
author:in the YAML header at the very top of this document to your name. The YAML header controls the style and feel for knitted document but doesn’t actually display in the final output.Next, click the knit button in the toolbar above to “knit” your R Markdown document to a HTML file that will be saved in your R Project folder. You should see a formatted webpage appear in your Viewer tab in the lower right pan or in a new browser window. Let your instructor know if you run into any issues with knitting.
Finally, publish your webpage on Rpubs by clicking the “Publish” button located in the Viewer Pane after you knit your document.
Your First Machine Learning Badge
Congratulations, you’ve completed your first badge activity! To receive credit for this assignment and earn your first official Lab Badge, submit the link on Blackboard and share with your instructor.
Once your instructor has checked your link, you will be provided a physical version of the badge below!