Statistics and variable types

Describe how you might use statistics in your everyday life?

Answer: there are some statistics, which are used in our everyday life.

1. Weather forecasts

2. Emergency preparedness

3. Medical studies

4. Insurance

5. Consumer Goods

What is the difference between populations and samples?

Answer:

Explain how interval and ratio scales differ.

Explain how ordinal and nominal variables differ.

Understanding Graphs

1. It is believed that hunger is partly controlled by external (environmental) cues. To investigate this a random sample of 60 first year students was selected and each student was in turn randomly allocated to one of three groups. Each group of 20 students was put into a room with a large clock prominently displayed on the wall, and asked to complete a questionnaire. In the first room, the clock on the wall showed the correct time. In the other rooms the clock was either one hour fast or one hour slow. The actual time, 5.30pm, was the usual evening meal time for all of the students. While the participants filled out the questionnaire, some dry biscuits and cheese were freely available. The weight of the biscuits and cheese consumed by each student was calculated; the means were: 4.30 group, 200gm; 5.30 group, 300gm; and 6.30 group, 400gm. Identify the following:

the dependent variable

the independent variable

a population of interest

a sample

a statistic that was calculated

a variable measured on a nominal scale

a variable measured on a ratio scale

What did this study find?

Understanding descriptive statistics

In what way does the median represent the middle of the distribution?

In what way is the mean the balancing point of a distribution?

Calculate the mean and the median for the following data values:

5, 7, 8, 2, 3, 8;

1.2, 0.8, 1.1, 0.6, 25

Why doesnt it make sense to add up the numbers on the back of football jumpers to get an average?