G4 Statistics Finals Flashcards

Front

Why is it important to calculate the spread as well as the mean for a data set?

Back

It's important to get the spread and mean of the data as it helps in getting a complete and accurate understanding of the data’s characteristics such as its variability.

Front

What are the properties of a binomial experiment?

Back

A Binomial Experiment’s properties include: Binary outcomes (success or failure), independent trials, number of trials is fixed, and same probability of success. (BINS)

Front

What are the advantages of sampling?

Back

Sampling greatly reduces the volume of data, saves time, and gets you an accurate result that does not require examination of an entire data set.

Front

Under what conditions does the sampling distribution approximate the normal distribution for means and proportions?

Back

Sampling distributions for means approximate normal distributions when the sample doesn't have any sort of notable skew or outlier (alternatively, if the sample is above 30, then central limit theorem ensures that the distribution will become normal.) Sampling distributions for proportions approximate normal distributions when np ≥ 10 and n(1 - p) ≥ 10.

Front

How do we know when to fail to reject/reject the null hypothesis in a significance test?

Back

Use the p-value and compare it to the significance level (usually α=0.05). Reject the null hypothesis if p ≤ α. Fail to reject the null hypothesis if p ≥ α.

Front

Explain the null hypothesis and the alternative hypothesis in significance testing.

Back

The null hypothesis is the starting assumption and the alternative hypothesis is what you want to prove.

Front

When given raw data and asked to perform a statistical analysis on it, how should you first examine the data? What are you looking for?

Back

You should first look to see whether the data is quantitative or categorical. If it is quantitative, you should look at the shape, outliers, center, and variability. If it is categorical, you should look for Marginal relative frequency, Relative frequency, Joint relative frequency, and Conditional relative frequency.

Front

What are the measures of center of data? When would each be used?

Back

The measures of center of data are Mean, Median, and Mode. The mean calculates the average of the data and is generally used when you have no outliers and when the distribution is symmetric. The median is the middle value in a data set and is generally used when there is a skewed distribution or outliers.

Front

In what ways can we build randomization into data collection?

Back

To build a randomized data collection you can use things such as a random number generator or flip a coin. We do this when random sampling from a population or randomly assigning in an experiment.

Front

What are the steps in a simulation of an event?

Back

Assign digits to each outcome, choose numbers at random, calculate probability based on the result of outcome.