# Problem Set 1

## DUE DATE: Thursday, March 1

• This is an example of a formal writing exercise where you will prepare a formal report.

• In fact, you should consider each question as a separate short report that should include an introduction, main body, and a conclusion. The introduction can be short; few sentences that explain the purpose of the exercise and provide definitions and/or equations used in the main body.

• When you are writing your reports, you should assume that the reader does not know what the guiding question is. In other words, each of your answers should be able to be read as a stand alone report. In addition, the report should be written for a general audience with a limited knowledge of nutrition and economics.

• If you are including tables, graphs, diagrams, figures, each item should include a number, title, and a source.

• Here are some guidelines to writing a good report: https://www.wikihow.com/Write-a-Report. Since the topic is already assigned to you, you can skim Part 1: Selecting your topic and focus on Part 2: Researching your topic, Part 3: Prewriting your report, Part 4: Writing your report, and Part 5: Finalizing your report.

1. Few definitions

Directions:

a. What is BMI?

i. If a woman weighs 70 kg and is 172 cm tall, what is her BMI? Show your calculations. Should she be worried? Why/why not? What is the basal metabolic rate for this woman? Assume that she is 27 years old. Suppose that you also know that she is involved in heavy exercise. How many calories does she need to consume per day in order to maintain her weight? Show your calculations.

ii. If someone weighs 200 pounds and is 5 feet 7 inches, what is his BMI? Show your calculations. Should he be worried? Why/why not? What is the basal metabolic rate for this man? Suppose that he is 50 years old. Suppose that this man has a very sedentary lifestyle. How many calories does he need to consume per day in order to maintain his weight? Show your calculations.

b. What is the difference between prevalence of obesity and incidence of obesity?

c. What is a calorie?

2. Globesity

World Health Organization provides incredible data and information on health status of people across the globe. Of great interest to us in this course, they provide data on mean BMI and prevalence of oveweight and obesity around the world. In this question we will first focus on the prevalence of overweight and obese (BMI > 25).

Directions:

1. Go to the following site http://apps.who.int/gho/data/view.main.CTRY2430A?lang=en

3. In Excel appropriately sort the data

Using most current data - Year 2016

List the top 10 countries with the highest overweight and obesity prevalence for men, women, and both sexes.

List the top 10 countries with the lowest overweight and obesity prevalence for men, women, and both sexes.

What is the rankings for the US?

4. Carefully describe the data (one paragraph, 250 words) and what these numbers are saying (one paragraph, 250 words).

Now let us focus on the obesity prevalence (BMI > 30)

Directions:

3. In Excel appropriately sort the data and

List the top 10 countries with the highest obesity prevalence for men, women, and both sexes.

List the top 10 countries with the lowest obesity prevalence for men, women, and both sexes.

4. Carefully describe the data (one paragraph, 250 words) and what these numbers are saying (one paragraph, 250 words).

3. Calories

For this question we will use data provided by the US Department of Agriculture (USDA). USDA is the U.S. federal executive department responsible for developing and executing federal laws related to farming, agriculture, forestry, and food. Approximately 80% of the USDA's \$140 billion budget goes to the Food and Nutrition Service (FNS) program. The largest component of the FNS budget is the Supplemental Nutrition Assistance Program (formerly known as the Food Stamp program), which is the cornerstone of USDA's nutrition assistance.

In addition, the USDA's Economic Research Service provides, prepares, and updates incredible publicly available data related to farming, agriculture, forestry, and food.

In this questions, we will use USDA food availability data in order to study and analyze the changes in calorie consumption in the US from 1970-2010.

Directions:

1. Follow the link that will take you to the USDA food availability data: https://www.ers.usda.gov/data-products/food-availability-per-capita-data-system/

4. Prepare graphs that show what has been happening to the amount of calories consumed in the US between 1970 – 2010. Your graph(s) should include total calories, meat, eggs and nuts, dairy, fruits and vegetables, flour and cereals products, added fats, and added sugar.

5. Describe the data and analyze your graphs.

6. Have Americans changed the amount of calories they eat since 1970? How? What does this mean? How does this help explain the obesity epidemic in the US?

4. Expenditure Shares

This questions again relies on the data provided by the USDA. The purpose of this questions will be to study changes in income expenditure from 1953 - 2014. More precisely, we will study the changes in income expenditures on food at home and food away from home.

Directions:

5. Prepare a graph that shows food expenditure on food at home and food away from home in real 1988 prices between 1953 and 2014.

6. Describe the data and analyze your graphs. Make sure that you define what is meant by the "food at home" and "food away from home".

7. Have Americans changed their eating habits? How? What does this mean? How does this help explain the obesity epidemic in the US?

5. Real Food Prices (Part I)

For this question we will use data provided by the Bureau of Labor Statistics. The Bureau of Labor Statistics (BLS) is a unit of the United States Department of Labor. The BLS is a governmental statistical agency that collects, processes, analyzes, and disseminates essential statistical data to the American public.

Directions:

• Part 1: Get Food Prices

1. Go to bls.gov.

2. Under “Subjects” select Consumer Price Index.

3. Click on CPI Data - Databases

4. Under Average Price Data click on “Multi-screen Data Search”

5. Select “U.S. City Average”,

6. Select a food category. For example, select "Eggs, grade A, large, per doz"

7. Click on Retrieve Data

8. Your data will show up in a new window. The first thing you should do is to select the beginning year to go as far back as possible under “From:” drop down menu and then press blue “Go” button.

10. Once you have your data in excel, calculate the average yearly price.

• Part 2: Get CPI

In order to calculate real prices you will need CPI for all items.

1. Go back to CPI Databases

2. Under “All Urban Consumers (Current series)” select “Multi-screen data search”

3. Select “Seasonally adjusted == > “U.S. city average” ==> Current ==> All items” ==> Monthly ==> Retrieve data.

4. Your data will show up in a new window. The first thing you should do is to select the beginning year to go as far back as possible under “From:” drop down menu and then press blue “Go” button.

6. Calculate yearly average CPI.

7. Once you have CPI calculated for your years add them to your food price Excel spreadsheet that you prepared in Part 1.

Make sure that the years for CPI match the food prices and that everything is properly aligned!

• Part 3: Convert Food Prices into 2017 (Constant Dollars) and plot your answers

"Current dollars" are what we usually mean when we refer to a currency in the current time period. The term "constant dollars" refers to dollars of several years expressed in terms of their value ("purchasing power") in a single year, called the base year. This type of adjustment is done to eliminate the impact of widespread price changes.

Current dollars are converted to constant dollars using an index of price movements. The most widely used index for household or family incomes, provided that no specific uses of the income are identified, is the Consumer Price Index (CPI), which reflects average spending patterns by consumers in Canada.

The following table shows the annual rates of the Consumer Price Index. To convert current dollars of any year to constant dollars, divide them by the index of that year and multiply them by the index of the base year you choose (remember that the numerator contains the index value of the year you want to move to). For example, suppose that the price in 1970 is \$2.20 and you would like to convert it into 2017 dollars. You need CPI in 1970 and CPI in 2017, which are 38.84 and 245.14 respectively. Use the equation \$2.20 x 245.14/38.84 = \$13.89. This means that \$2.20 in 1970 is equivalent (has the same purchasing power) as \$13.89 in 2017.

1. Calculate “real” prices or price in 2017 dollars.

2. Prepare a graph for those prices over time.

3. Describe the data and describe the graph you created. What has happened to the price of your selected food item overtime?

You should get data for at least 5 food items and “Gasoline, unleaded regular, per gallon”.

Below is a graph for all Eggs, grade A, large, per dozen.

6. Real Food Prices (Part II)

The purpose of this exercise is to analyze the change in food prices relative to the increase in prices for all other items. Have the food prices been increasing faster than overall inflation? Or is food today relatively less expensive than in the past?

Directions:

• Part 1: Get Food Prices

1. Go to bls.gov.

2. Under “Subjects” select Consumer Price Index.

3. Click on CPI Data - Databases

4. Under “All Urban Consumers (Current series)” select “Multi-screen data search”

5. Select “NOT Seasonally adjusted == > “U.S. city average” ==> Current ==> Select the following 8 series:

1. All items

2. Food and beverages

3. Food at home

4. Cereals and bakery products

5. Meats, poultry, fish, and eggs

6. Fruits and vegetables

7. Other food at home

8. Alcoholic beverages == > Monthly ==> Retrieve data

6. Your data will show up in a new window. The first thing you should do is to select the beginning year as 1967 under “From:” drop down menu, click on "Include annual averages", and then press blue “Go” button.