Introduction
My group and I designed a survey to learn more about the chesseburger consumption of our friends and coworkers. The population that we sampled is adults. We did not obtain a random sample for this survey. Instead, we polled our Facebook friends, and coworkers. Therefore we have a convenience sample with a voluntary response aspect, as not everyone we asked took the time to respond.
We asked the following questions:
1. How many times a month do you eat cheeseburgers?
2. How many different resturants do you dine at for cheeseburgers?
3. Do you always eat fries with your cheeseburger? yes/no
4. How do you like your burger cooked? rare/mediumrare/medium/mediumwell/well
Looking at a Categorical Variable
The responses to the question "How do you like your burger cooked?" are shown in the pie chart below.

It can be seen that nearly three quarters of the people surveyed perfer their burgers cooked Medium, while 10% like MediumRare. Only 5% perfer Rare, MediumWell, and WellDone.
In order to see if the choice of ways in which burgers are cooked amoung people whom like fries with their cheeseburgers we can examine the bar plot below.

Among people whom eat fries with their burgers and do not, the most frequent choice is to eat their burger cooked medium. However, the choice of a medium cooked burger is slightly higher in the group of people whom perfer fries with their burgers.
Looking at a Numerical Variable
The response to the question "How many times a month do you eat burgers?" are shown below in the histogram, boxplot, and summary statistics.


Summary statistics:

The histogram shows a right skewed distribution with most of the data less than 6 times per month. The modal class of the histogram is 26 times per month.
The center of the skewed data set is best described by the median, which is not affected by the extreme values. Here the median is 3 times eating burgers per month, while the mean is 3.38 hours. The midrange, (0+9)/2 is 4.5 hours, which is not is not a reasonable measure as we can see in the histogram. The mean is greater than the median which we would expect with the rightskew.
There is some variability in the responses to this question, with a range of 9 times per week and a standard deviation of 2.21. For this data the range rule of thumb is = 2.25 and the standard deviation is 2.21. The skewness of the data and the outliers make the range rule of thumb overestimate the standard deviation.
The boxplot reveals the outliers which I determined them to be 8 and 9. These values represent eating cheeseburgers 89 times per month although they are possible, for an average healthy adult I would consider them to be unreasonable.
Looking for a Relationship between Two Numerical Variables
To decide whether there is a relationship between the responses to the questions "How many cheeseburgers do you eat per month?" and "How many different resturants do you dine at for cheeseburgers? we look at the scatter plot of the paired data.

The scatter plot reveals positive trend with a large amout of scatter. Three outliers stand out 5 different resturants to dine at for cheeseburgers .
The correlation coefficent for the paired data is .534, as shown below
Correlation between How many times a month do you eat Cheeseburgers and How many Resturants do you dine out for Cheeseburgers is:
0.53357595 
Since the absolute value of r is more than .196, we can say that there is a signicant correlation between the number of times per month people eat cheeseburgers and how many resturants people dine at to eat cheeseburgers. However, the scatter plot reveals that association between the two is not strong.
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