The Basics of Statistics used in Food Science

You probably use the processes of finding the Mean, Median, Mode and Range almost every day without even realizing it?!?

Mean

Median

Mode

Range

% Difference

& how to use these in everyday life,

as well as in our Food Science results!

You should have a pencil, a piece of paper, and a calculator if you need one.

Mean, Median, Mode & Range…

What about the words we already know: Average, Middle, Most Frequent, and Difference?

They are all the same ideas!

The mean is the Average of a group of numbers

It is helpful to know the mean because then you can see which numbers are above and below the mean

Example test scores for our Food Science class: 82 93 86 97 82

To find the Mean, first you must add up all of the numbers.

82 + 93 + 86 + 97 + 82= 440

Now, since there are 5 test scores, we will next divide the sum

by 5.

440÷5= 88

The Mean is 88!

The Median is the middle value on the list.

The first step is always to put the numbers in order.

First, let’s examine these five test scores. 78 93 86 97 79

We need to put them in order.

78 79 86 93 97

The number in the middle is 86 78 79 86 93 97

In this case, the Median is 86!

Now, let’s try it with an even number of test scores.

92 86 94 83 72 88

First, we will put them in order 72 83 86 88 92 94

This time, there are two numbers in the middle, 86 and 88

72 83 86 88 92 94

Now we will need to find the Average of these two numbers,

by adding them and dividing by two.

86+88= 174 174÷2= 87

Here the Median is 87

The Mode refers to the number that occurs the most frequently.

It’s easy to remember…

The first two numbers are the same! MOde and MOst Frequently!

Here is an list of temperatures for one week.

Mon. Tues. Wed. Thurs. Fri. Sat. Sun.

77° 79° 83° 77° 83° 77° 82°

Again, We will put them in order.

77° 77° 77° 79° 82° 83° 83°

77° is the most frequent number, so the mode= 77°

The range is the difference between the highest and the lowest numbers of the series.

All we have to do is put the numbers in order and subtract.

Let’s look at the temperatures again.

77° 77° 77° 79° 82° 83° 83°

The highest number is 83, and the lowest is 77.

All you need to do is subtract!

83-77= 6

In this case, the Range is 6

This is the Stat Family!

Dad Mom Jack Alex Katie

34 33 5 5 1

Here are the ages again…

Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1

What is the Mean?

Remember… Mean is the AVERAGE

Try it on your paper and see what you come up with!

Remember, to find the mean, we have to first add up all of the numbers.

34+33+5+5+1= 78

Then, since there are 5 people in the family, we next divide by 6.

78÷5= 15.60

The Mean in this case is 15.60 (use 2 decimals)

Here are the ages again…

Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1

What is the Median?

Remember… Median is the MIDDLE NUMBER

Try it on your paper and see what you come up with!

Remember, to find the mean, we have to first put all of the numbers in order.

34 33 5 5 1

The Mean in this case is 5

Here are the ages again…

Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1

What is the Mode?

Remember… Mode is the MOST FREQUENT

Try it on your paper and see what you come up with!

Remember, to find the mode, we have to first put all of the numbers in order.

34 33 5 5 1

The Mode in this case is 5

Here are the ages again…

Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1

What is the Range?

Remember… Range is the DIFFERENCE

Try it on your paper and see what you come up with!

Remember, to find the range, we have to first put all of the numbers in order.

34 33 5 5 1

The highest age is 34, and the lowest is 1

Now we need to subtract to find the difference

34-1= 33

The range is 33

When you have multiple trials of an experiment, you will need to determine the % between trials

Sometimes scientists want to compare their results with those of others

Each of these types of comparisons call for a different type of analysis, percent difference and percent error respectively.

RANGE X 100

MEAN

Range: 33

Mean: 15.60

X100 = 211.54%