Investigating data Flashcards
What is the mean?
The mean is the average score.
What is the mode?
The mode is the most frequent score.
What is the median?
The median is the middle score arranged in ascending order.
What is the range
The range is the range between the highest and lowest scores.
What is the mean of the scores 3, 6 and 7?
3+6+7/3
= 16/3
mean = 5.3
What is the mean of the scores 5, 10 and 15?
5+10+15/3
= 30/3
mean = 10
What is the mean of the scores 2, 4, 7 and 10?
2+4+7+10/4
= 23/4
mean = 5.6
What is the cumulative frequency?
The cumulative frequency is a running total of frequencies.
What is a frequency histogram?
A frequency histogram is a collumn graph of numerical data where the columns stand together with no gaps between.
What is a frequency polygon?
A frequency polygon is a line graph constructed by joining the midpoints of the frequency histogram bars.
What is a stem and leaf plot?
A stem and leaf plot lists the scores of a dataset in order.
What are the 4 shapes of distribution. Describe.
- Symmetrical, a shape of distribution where there are more scores in the middle then there are on the end and the front.
- Bimodal, a shape of distribution where there are two humps with a dip in the middle.
- Skewed (negative), a shape of distribution with more scores near the end then at the front.
- Skewed (positive), a shape of distribution with more scores near the front then at the end.
What is a census/sample?
A census is when a small group of people are selected opposed to a whole group. (less accurate)
A sample is when a whole group of people are selected opposed to a small group. (more accurate)
What is catagorical/numerical (continuous and discrete) data?
Catagorical is when numbers are used instead of numbers.
Continuous numerical data is when decimals are used.
Discrete numerical data is when whole numbers are used.