Tag Archives: QL

How can ocean temperature profiles connect to calculus?

Exploring Our Fluid Earth has some educational materials for science. For example, the page Compare-Contrast-Connect: Seasonal Variation in Ocean Temperature Vertical Profiles includes the graph copied here.  Some of these graph have inflection points which relate (I think) to thermoclines (transition between warmer surface water and colder deep water). There certainly seems to be a calculus connection here. For QL folks the graphs are a little tricky based on the y-axis and math folks would probably prefer the depth as the x-axis (why?). There are links on the right sidebar to other projects and information.

Is there a relationship between homicide and race?

One more post from the Manhattan Institute’s* Breaking Down the 2020 Homicide Spike by Christos A. Makridis and Robert VerBruggen (5/18/2022). We first note:

Homicides went up throughout the country, and for every major demographic group, in 2020, but they did not rise for everyone equally, as is clear when we break down the numbers by race, age, sex, urbanicity, and region of the country.

Related to figure 3 (copied here) we have this, which is excellent  QL material:

The racial and ethnic breakdown is perhaps most striking in this regard. Proportionally, homicide rates rose by about 34% for black Americans and about 19% percent for non-Hispanic whites: a notable, but not extreme, gap (Figure 3). But since the black homicide rate was already many times higher than the white one, this translated into 8 additional black deaths for every 100,000 population—an increase similar to the total homicide rate for the country as a whole—while the death rate for whites rose by only 0.5 per 100,000. (Recall that these numbers pertain to the homicide victims, not the killers, though American homicide is overwhelmingly intraracial.)

There is a lot to discuss in this article as well as ample quantitative literacy material. There is a discussion of methods and the CDC data they use is easy enough to locate.

* (This is the same note from Monday’s Post) Yes, MI has a clear political leaning but that doesn’t make their work incorrect. Their data and methods are sound here and this should be engaged not ignored. If someone thinks something is incorrect then let me know.

 

 

Is there a correlation between Homicide rate and voting?

The Manhattan Institute* has a lengthy report on the increasing homicide rate, Breaking Down the 2020 Homicide Spike by Christos A. Makridis and Robert VerBruggen (5/18/2022), with numerous interesting charts. From the report (figure 7 copied here):

Next, we explore the correlation between two geographic factors—population and GOP vote share—and the growth rate in the homicide rate per capita between 2019 and 2020. Each observation is a county whose size is determined by its population, giving larger counties greater weight. Counties with a higher share of GOP voters not only have lower homicide rates but also a lower growth in homicide rates between 2019 and 2020 (Figures 6 and 7).

There is a positive correlation between population in a county and the growth in the homicide rate, but the correlation between population and just the homicide rate is slightly negative (Figure 8). In this sense, even though there are slightly higher rates of homicide deaths per capita in smaller counties, some of those differences could be driven by spurious factors that are correlated with population.

There is a lot to discuss in this article as well as ample quantitative literacy material. There is a discussion of methods and the CDC data they use is easy enough to locate.

* Yes, MI has a clear political leaning but that doesn’t make their work incorrect. Their data and methods are sound here and this should be engaged not ignored. If someone thinks something is incorrect then let me know.

 

How big is the Dem/Rep perception gap?

More in Common did a perception gap study in 2018 and while it is a few years old it is worth reading. The graph copied here is the Democrats’ Perception Gap and the page has a similar one for Republicans. One interesting paragraph:

Education is intended to make us better informed about the world, so we’d expect that the more educated you become, the more you understand what other Americans think. In fact, the more educated a person is, the worse their Perception Gap – with one critical exception. This trend only holds true for Democrats, not Republicans. In other words, while Republicans’ misperceptions of Democrats do not improve with higher levels of education, Democrats’ understanding of Republicans actually gets worse with every additional degree they earn. This effect is so strong that Democrats without a high school diploma are three times more accurate than those with a postgraduate degree.

The page has 11 graphs and would make a great QL source for discussion in a class. One key question to ask is if the gap has gotten better or worse over the last few years.

How many billion dollar disasters in 2021?

The NOAA Billion-Dollar Weather and Climate Disasters page keeps track of these events.

During 2021, there were 20 separate billion-dollar weather and climate disaster events across the United States. The total cost from these events of 2021 was $145.0 billion and is the third most costly year on record, behind 2017 and 2005. The total costs for the last five years ($742.1 billion) is more than one-third of the disaster cost total of the last 42-years (1980-2021), which exceeds $2.155 trillion (inflation-adjusted to 2021 dollars). This reflects a 5-year cost average of nearly $148.4 billion/year — a new record — as shown above by the black line.

The chart copied here is interactive on their page and has lots of information. You can also select a state or region and get a similar chart. Data can be downloaded.

What are the trends in drug overdose deaths?

The Pew article Recent surge in U.S. drug overdose deaths has hit Black men the hardest by John Gramlich (1/19/2022) provides the graph copied here.

Nearly 92,000 Americans died of drug overdoses in 2020, marking a 30% increase from the year before, a 75% increase over five years and by far the highest annual total on record, according to the Centers for Disease Control and Prevention (CDC). Preliminary figures suggest that the 2021 death toll from overdoses may be even higher.

Overall

While overdose deaths in the U.S. were on the rise long before the outbreak of COVID-19 in March 2020, such fatalities have accelerated during the pandemic, the CDC has noted.

Nationwide, the monthly number of drug overdose deaths had never exceeded 6,500 before March 2020. Between March and December 2020, there were more than 7,100 such deaths each month, including nearly 9,400 in May 2020 alone.

There does not appear to be direct links to the data but there is plenty of quantitative info in the article.

Which party can speak more freely?

The Pew article Republicans continue to see a national political climate more comfortable for Democrats than for GOP by Bradley Jones (12/8/2021) is another example of the disconnect in the U.S.

When Republicans take stock of the national climate for political discourse, they see a much more hospitable environment for Democrats than for members of their own party. About six-in-ten Republicans and Republican-leaning independents in the United States (63%) think that “Democrats in this country are very comfortable to freely and openly express their political views,” but only about two-in-ten (19%) think Republicans around the nation experience that same level of comfort.

Responses from Dems go the other way but aren’t as extreme. Pew provides the questions asked and the methodology.

Where is the center of the U.S population?

Before we get to where the center of the U.S. population is maybe we should say what it is. From the U.S. Census Bureau’s article The “Hart” of the Nation’s population: Hartville, Missouri (pop. 594) (11/165/2021):

Every decade since the first census in 1790, the Census Bureau has used data from each decennial census to calculate the center of population — the point where the country would balance perfectly on a flat map if everyone had the same weight of one.

In addition to a national center of population, the Census Bureau also calculates centers of population for each state, county, census tract and census block group. Coordinates for each of these locations can be found on the Centers of Population webpage.

The map here shows the center and how it has moved since 1790. This is near the bottom of the article and it is interactive in that users can choose individual states. The link in the quote will take users to a page with lat and lon for the mean and median centers of each state.

Has much has poverty decreased?

The Our World in Data article Extreme poverty: how far have we come, how far do we still have to go by Max Roser (11/22/2021) provides numerous graphs that quantify changes in poverty. The most general graph is copied here. This one is for the world but users can select specific countries instead of the world to produce a related graph.

The overall conclusion is summed up well by their summary:

Two centuries ago the majority of the world population was extremely poor. Back then it was widely believed that widespread poverty was inevitable. But this turned out to be wrong. Economic growth is possible and poverty can decline. The world has made immense progress against extreme poverty.

But even after two centuries of progress, extreme poverty is still the reality for every tenth person in the world. This is what the ‘international poverty line’ highlights – this metric plays an important (and successful) role in focusing the world’s attention on these very poorest people in the world.

The poorest people today live in countries which have achieved no growth. This stagnation of the world’s poorest economies is one of the largest problems of our time. Unless this changes millions of people will continue to live in extreme poverty.

 

There are some distribution type graphs that could be useful for statistics classes and most of the graph have an option to download the data.

Why are more women completing college than men?

The Pew article What’s behind the growing gap between men and women in college completion? by Kim Parker (11/8/2021) notes:

Men are more likely than women to point to factors that have more to do with personal choice. Roughly a third (34%) of men without a bachelor’s degree say a major reason they didn’t complete college is that they just didn’t want to. Only one-in-four women say the same. Non-college-educated men are also more likely than their female counterparts to say a major reason they don’t have a four-year degree is that they didn’t need more education for the job or career they wanted (26% of men say this vs. 20% of women).

Women (44%) are more likely than men (39%) to say not being able to afford college is a major reason they don’t have a bachelor’s degree. Men and women are about equally likely to say needing to work to help support their family was a major impediment.

Also worth noting:

The reasons people give for not completing college also differ across racial and ethnic groups. Among those without a bachelor’s degree, Hispanic adults (52%) are more likely than those who are White (39%) or Black (41%) to say a major reason they didn’t graduate from a four-year college is that they couldn’t afford it.

There is information about the questions and methodology.