
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given the following 4 propositions, the correct proposition numbers are.

(1) In a large number of experiments, the frequency of event $A$ can be used as an estimate of the probability of event $A$ occurring;

(2) The sample standard deviation $S= \sqrt{ \frac{(x_{1}- \bar{x})^{2}+(x_{2}- \bar{x})^{2}+...+(x_{n}- \bar{x})^{2}}{n-1}} (n\geqslant 2)$ can be used as a point estimate of the population standard deviation;

(3) Random sampling is a sampling method that allows every individual in the population to have the same possibility of being selected into the sample;

(4) Stratified sampling is a sampling method that divides the population into several parts, and then specifies certain individuals in each part as the sample.

Present the answer in LaTex format: \boxed{Your answer}
user