PSYC test inferential stats

Question 1

What are descriptive statistics?

Answer 1

descries data (bar chart or graph)

Question 1

What are inferential statistics?

Answer 1

allows you to make predictions from the data. You take data from samples and make generalization about a population

Question 2

When we sample individuals from a population, what do we assume?

Answer 2

We assume that the sample is representative of the population

Question 3

Why do we compute statistics of our sample?

Answer 3

To help us make inferences about the parameters of the population

Question 4

Why will our statistics not match our parameters precisely?

Answer 4

Due to sampling error

Question 5

What is a population parameter? What symbols describe it?

Answer 5

a summary that describes the population using greek letters. u is mean

Question 6

What is a sample statistic? What symbols describe it?

Answer 6

a summary that describes a sample using the latin alphabet. x bar is mean

Question 7

Will the results be identical if we draw more than one sample from the same population?

Answer 7

No

Question 8

How do the sample means estimate the population mean?

Answer 8

Each is a bit different and the average of all the sample means is the population mean

Question 9

What is one sample mean a part of?

Answer 9

A distribution of possible sample means

Question 10

What happens to sample means with larger samples

Answer 10

less variation

Question 11

The larger the sample, the better it can estimate the population mean. What does this mean? What happens to variation between samples?

Answer 11

larger samples end up closer to the population mean and closer to each other –> less variation between samples

Question 12

What happens if you repeatedly samples from any population?

Answer 12

regardless of the shape of the population distribution, the distribution of sample means will tend towards a normal distribution

Question 13

What would be true about the distribution of many sample means from the same population

Answer 13

The distribution would be normal
The mean would be the same as the population mean
The standard deviation of the sample means would be smaller than the population SD –> standard error

Question 14

What does it mean by the the distribution would be norma with large enough samples?

Answer 14

if you take many samples from the same population and plot the distribution of those sample means, it will tend to follow a normal distribution

Question 15

What does it mean by the mean would be the same as the population mean?

Answer 15

average of all the sample means would be equal to the population mean.

Question 16

What does it mean by the standard deviation of the sample means (standard error) would be smaller than the population SD

Answer 16

because when you take multiple samples and calculate their means, the variability of those means tends to be smaller than the variability of individual observations in the population.