Can someone run me through this thing like what is a random sample collection or what is categorial etc because i wasnt in g maths for year 11 so don't understand the concepts of these was never taught and theres usually always atleast 1 in the exam
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Random, Categorial etc (1 Viewer)
- Thread starter Picle
- Start date
There are two different things you'll need to know:
Types of Data
1. Categorical
For example, favourite colour, brand of toothpaste you use, brand names, words, etc.
2. Numerical
There are two types of numerical data:
A: Continuous, like a person's height, weight, body temperature, etc.
B: Discrete, like the number of cars in your family, the number of children in your house, the number of pets you have.
So there can be Categorical data, Discrete Numerical data or Continuous Numerical data.
Also, you wouldn't use mean or median for categorical data, just mode because they're not numerical values.
Types of Random Sampling
1. Random Sampling
For example drawing names out of a hat, randomly generated numbers, etc.
2. Systematic Sampling
For example, choosing every 10th person from a list of names, or testing every 100th item on a production line.
3. Stratified Sampling
This one is more complicated. Say your class has 50 students, 10 male and 40 female. You need to pick a focus group or something from your class of 5 students. Then using stratified sampling, you should pick 1 male and 4 females so the ratio of the students stays the same.
You need 5 out of 50 students = 5/50 = 1/10.
So choose 1/10 of male students = 1/10 x 10 = 1
And choose 1/10 of female students = 1/10 x 40 = 4
That gives how many of each you should pick, and then you could use random sampling or systematic sampling to pick the 1 male or 4 females from the class.
Hope this helps a little bit.
Types of Data
1. Categorical
For example, favourite colour, brand of toothpaste you use, brand names, words, etc.
2. Numerical
There are two types of numerical data:
A: Continuous, like a person's height, weight, body temperature, etc.
B: Discrete, like the number of cars in your family, the number of children in your house, the number of pets you have.
So there can be Categorical data, Discrete Numerical data or Continuous Numerical data.
Also, you wouldn't use mean or median for categorical data, just mode because they're not numerical values.
Types of Random Sampling
1. Random Sampling
For example drawing names out of a hat, randomly generated numbers, etc.
2. Systematic Sampling
For example, choosing every 10th person from a list of names, or testing every 100th item on a production line.
3. Stratified Sampling
This one is more complicated. Say your class has 50 students, 10 male and 40 female. You need to pick a focus group or something from your class of 5 students. Then using stratified sampling, you should pick 1 male and 4 females so the ratio of the students stays the same.
You need 5 out of 50 students = 5/50 = 1/10.
So choose 1/10 of male students = 1/10 x 10 = 1
And choose 1/10 of female students = 1/10 x 40 = 4
That gives how many of each you should pick, and then you could use random sampling or systematic sampling to pick the 1 male or 4 females from the class.
Hope this helps a little bit.
appreciate itSlaminSammy
Member
NOTE!
I have found that in every question regarding the type of data they are stipulating there is always an easy way to tell
Quantitative (discrete) always has the word NUMBER in the line for example - number of cars or number of patients or number of students - they are all examples of data that is quantitative (discrete). Remember to look out for number in multiple choice or 1 mark questions and you should pick it up really quickly. KEEP IT TO YOUR SELVES
Quantitative (continuous) is always refering to measurments of something. For example - The weight of chubby little cats or the circumference of one of J LOs ass cheecks or volume of one - can also be the area of playgrounds in metropolitan sydney - what ever... you better understand that!
(heard a good joke about that --> New york has experienced 10 days of continuous rain - and the Wax museum flooded - Security officers found a family of Asian tourists hugging Jlos butt to stay alive)
Lastly - Categorical - ITS NOT ONE OF THE OTHER TWO ---> a measurment of the types of Dogs a family has is not quantitative (continuous) dont get that wrong
I have found that in every question regarding the type of data they are stipulating there is always an easy way to tell
Quantitative (discrete) always has the word NUMBER in the line for example - number of cars or number of patients or number of students - they are all examples of data that is quantitative (discrete). Remember to look out for number in multiple choice or 1 mark questions and you should pick it up really quickly. KEEP IT TO YOUR SELVES
Quantitative (continuous) is always refering to measurments of something. For example - The weight of chubby little cats or the circumference of one of J LOs ass cheecks or volume of one - can also be the area of playgrounds in metropolitan sydney - what ever... you better understand that!
(heard a good joke about that --> New york has experienced 10 days of continuous rain - and the Wax museum flooded - Security officers found a family of Asian tourists hugging Jlos butt to stay alive)
Lastly - Categorical - ITS NOT ONE OF THE OTHER TWO ---> a measurment of the types of Dogs a family has is not quantitative (continuous) dont get that wrong