GIS Homework 4 - Mapping Using the American Community Survey - Change Mapping

Percent Vacant housing units for 2011, Cenus Tracts, Harris County, TX

Vach11<-get_acs(geography = "tract",
                state="TX",
                county = "201",
                year = 2011,
                variables="DP04_0003P" ,
                geometry = T,
                output = "wide",
               progress_bar=F ) %>%  
  mutate(PVHU = DP04_0003PE,
         PVHU_er = DP04_0003PM/1.645,
         PVHU_cv =100* (PVHU_er/PVHU)) %>%
  filter(complete.cases(PVHU), is.finite(PVHU_cv)==T)%>%
  select(GEOID, PVHU, PVHU_er,PVHU_cv)

head(Vach11)

Percent Vacant housing units for 2019, Census Tracts, Harris County, TX

Vach19<-get_acs(geography = "tract",
                state="TX",
                county = "201",
                year = 2019,
                variables="DP04_0003P" ,
                geometry = T,
                output = "wide",
                progress_bar=F) %>%  
  mutate(PVHU19 = DP04_0003PE,
         PVHU_er19 = DP04_0003PM/1.645,
         PVHU_cv19 =100* (PVHU_er19/PVHU19)) %>%
  filter(complete.cases(PVHU19), is.finite(PVHU_cv19)==T)%>%
  select(GEOID, PVHU19, PVHU_er19,PVHU_cv19)

head(Vach19)

Mapping Percent Vacant Housing Units for 2011 & 2019, Census Tracts, Harris County, TX

Calculating the differences between the two years (2011 & 2019), including the test for significance of the differences

# Make one of the dataset a non sf class dataset
Vach19_df <- Vach19 %>% 
  data.frame() %>% 
  select(-geometry)

 # Then merge the non sf class dataset to the sf class dataset 
Vach1119 <- left_join(Vach11, Vach19_df, by=c("GEOID"="GEOID")) %>% 
   na.omit()

#calculate the change between the percent vacant housing unit in 2011 and 2019
diff1119<-acstest(names = Vach1119$GEOID,
                    geoid =Vach1119$GEOID,
                    est1 = Vach1119$PVHU,
                    est2 = Vach1119$PVHU19,
                    err1 = Vach1119$PVHU_er,
                    err2=Vach1119$PVHU_er19,
                    alpha = .1,
                    yr1 = 2011, yr2=2019,
                    span = 4)

# Then merge the diffences dataset with the Vach1119
Mergediff <- left_join(Vach1119, diff1119, by=c("GEOID"="geoid")) 

head(Mergediff)

Mapping Differences In Percent Vacant Housing Units Between 2011 & 2019, Census Tracts, Harris County, TX

Mapping Test For Significance of the Changes In Percent Vacant Housing Units Between 2011 & 2019, Census Tracts, Harris County, TX