---
title: "Math Camp field notebook"
subtitle: "Question, code, evidence, judgment"
format:
  html:
    toc: true
    code-fold: false
    embed-resources: true
execute:
  echo: true
  warning: false
  message: false
---

## Policy question

Write one descriptive or associational question. Name the population, outcome, comparison, and time period.

## Data and definitions

- **Source:** World Bank World Development Indicators
- **Retrieval or snapshot date:**
- **Unit of observation:** country-year
- **Indicators and units:**
- **Known limitations:**

```{r}
#| label: setup

library(tidyverse)

wdi <- read_csv(
  "../data/derived/math-camp-wdi-2000-2022.csv",
  show_col_types = FALSE
)
```

## First inspection

Before using an agent, predict what each check should reveal.

```{r}
#| label: inspect

glimpse(wdi)
count(wdi, year)
summarise(wdi, economies = n_distinct(iso3c))
```

## Analysis sample

Explain every filter and transformation in plain language.

```{r}
#| label: build-analysis-sample

# Replace this example with the variables for your selected policy track.
analysis_data <- wdi |>
  select(iso3c, country, year, income_level,
         gdp_per_capita_ppp, under5_mortality) |>
  filter(year >= 2000) |>
  mutate(log_income = log(gdp_per_capita_ppp))

stopifnot(
  !anyDuplicated(analysis_data[c("iso3c", "year")])
)
```

## Comparison

```{r}
#| label: figure
#| fig-cap: "Replace this caption with the population, variables, years, and units."

ggplot(analysis_data, aes(log_income, under5_mortality)) +
  geom_point(alpha = 0.4, na.rm = TRUE) +
  labs(
    x = "Log GDP per capita, PPP",
    y = "Under-five deaths per 1,000 live births"
  ) +
  theme_minimal()
```

Write the strongest descriptive or associational statement supported by the output.

## What this does not show

Name at least one limitation related to measurement, missingness, comparison, or causal interpretation.

## AI-use note

I used **[Codex / Claude Code / other]** to **[explain, generate, debug, review, or update]**. I provided it with **[public project context]**. I verified its contribution by **[tests, source comparison, clean render, or manual review]**. I revised or rejected **[important example]**. I remain responsible for the analysis and interpretation.

## Verification record

| Agent claim or change | Check performed | Result |
|---|---|---|
|  |  | Confirmed / contradicted / unresolved |