Cogs 105 final

What is inferential statistics?

Estimating the value of the population parameters. In this type of statistics you are trying to reach conclusions that extend beyond the immediate data alone. You can draw conclusions from the data.

What is descriptive statistics?

Organzies and describes data. Used to describe the basic features of the data in a study. They provide simple summaries about the sample and the measures.

What are the measures of central tendenacey?

Mean, median, and mode

What is mean?

Average

What is median?

The number in the middle

What is mode?

The most occurring number

What is variability?

The extent to which data points in a statistical distribution or data set diverge from the average or mean value. Variability also refers to the extent to which these data points differ from each other.

What are the four commonly used measures of variability?

Range
Mean
Variance
Standard deviation

What is range?

The difference between the highest and smallest values

What is variance?

It is a measure of dispersion. It is the average squared distance between the mean and each item in the population or in the sample.

What is standard deviation?

A numerical value used to indicate how widely individulas in a group vary. If individual observations vary greatly from the group mean, the standard deviation is big and vice versa.

What are frequency distributions?

Main purpose is to organize. Can use all types of measurement scales.

What are the four types of graphs?

Pie
Bar
histograms
Frequency polygons

What is a bar graph?

Use seperate bar for each piece of information . Good for ordinal or nominal data.

What is a histogram?

Only useful for a quantifiable variable. Good for interval or ratio data.

What are frequency polygons?

Uses line to represent frequencies. Good for interval or ratio data. Should start at zero.

What is unimodal?

A frequency distribution with one value clearly having a larger frequency than another.

What is multimodal?

The probability distribution of the outcomes from a multimodal experiment.

What is rectangular?

Used to present the data in the graphic form. Used for comparison of two sets of data.

What is hypothesis testing?

Estimate the porbability that a sample is representative of the total population within 2 standard deviations of the mean or the middle 95% of the distribution.

What is random sampling?

When every possible sample of 'n' subjects is equally likely to be chosen. This provides some protection against the sample unrepresentataive of the population. No subgroup would be over represented in the sample.

What is standard error?

The standard deviation of means. The larger our sample size the smaller our standard error.

What is a type 1 error?

When the null hypothesis is rejected when it is in fact true.

What is a type 2 error?

When the null hypothesis is false but is not rejected. This type of error is frequently due to small sample size.

What is a test statistic?

A quantity calculated from our sample of data. Its value is used to decide whether or not the null hypothesis should be rejected in out hypothesis test.

What is a critical value?

A threshold to which the value of the test statistic in a sample is compared to determine whether or not the null hypothesis is rejected.

What is the critical region also known as?

The rejected region.

What is the critical region set at?

.05 or 5%

What is a p-value?

The probability of getting a value of the test statistic as extreme as or more extreme than that observed by chance alone if the null hypothesis is true.

What do small p-values suggest?

That the null hypothesis is unlikely to be true.

What is a one sample t-test?

A test for answering questions about the mean where the data are a random sample of independent observations from an underlying normal distribution.

What is a two sample t-test?

Answers questions about the mean where the data are collected from two random samples of independent observations each from an underlying normal distrbution.

How do you calculate degrees of freedom?

n-1

What are correlations?

Reflects the dynamic quality of the relationship between varaibles.

What was Kello's lecture about?

Measuring semantic space. Animal cluster shit.

What is a relation?

Anything thhat says whether some elements have a particular relationship.

What is relational cognition?

Cognition that works with relative roles that objects play rather than on the features of these objects. The more complex the relation is, the more difficulty people have in making comparisons between them.

What are featured based categories?

Things that share the same properties.

What was Michelle's research about?

Perspective taking. Book, robot, water. Most people take the egocentric perspective.