Statistik tenta

Which of the following variables is categorical?

In a probability model, all possible outcomes together must have a probability of 1.

Probability calculations from a binomial distribution can be found using a Normal approximation for large sample sizes

From central limit theorem,if we draw an SRS from any population sampling distribution of the sample mean will be normal

Margin of error for confidence interval for mean,based on specified sample size n,increase as confidence level decreases

A valid probability is any number between -1 to 1.

Which plot helps you visualize the value of the correlation, r?

A probability histogram describes the probability distribution of a discrete random variable.

The margin of error for a 95% confidence interval for the mean decreases as the population standard deviation decreases.

Which statement about standardized z-score of value of a variable X,that has mean of m & standard deviation of s,is true

When sampling data from a large population, the mean of the sampling distribution is_______.

Binomial distributions represent ___________ random variables.

When examining a distribution of a quantitative variable, which of the following features do we look for?

A simple random sample should be used for the t procedure when the sample size is small

The marigin of error in a confidence interval captures errors that are present from random sampling only.

The larger the level of confidence, the _____ the confidence interval.

The second letter of a word in a text message is independent of the first letter of that word.

The correlation coefficient must always lie between –1.0 and +1.0.

Outliers do not have a large effect on the formation of confidence intervals

In a test of statistical hypotheses, what does the P-value tell us?

100 athletes is selected from a large high school.There are 15 football players. What´s the standard error of proportion

When using a histogram to display categorical values, you should make sure the categories are in alphabetical order.

The appearance of a histogram will change when you _______.

Suppose that A and B are two independent events with P(A) = 0.3 and P(B) = 0.3. What is P(A and B)?

Which of the following are independent trials?

Sample size required to obtain a confidenceinterval of specified margin of error m increase as confidence level increase

P-value obtain from two-sided significance test will be twice as large as the p-value that come from same onesidedtest

A valid probability is either 0 or 1

The Histogram shows data from 30 students who were asked "how much time do u spend on internet in minutes" what is shown

When the sample size is very large, the corresponding t distribution is very close to the normal distribution

A probability histogram describes the probability distribution of a discrete random variable

Outliers do not have a large effect on the formation of confidence intervals.

The _____ the P-value, the stronger the evidence against the null hypothesis provided by the data.

The one-sample z statistic is used instead of the one-sample t-statistic when _____.

The probability of success for binomial distribution must remain the same for each observation.

A probability histogram can only be used for continuous random variables.

Large sample significance tests for a single proportion are based on the _____.

Let random variable X be number of repair calls an appliance repairshop receive during 1h.Distribution of x given below

Probability calculations from t procedure are valid if theres outliers indata as long as sample size is large/datanormal

Two events are considered independent if the outcome of one does not influence the outcome of the other.

The purpose of forming confidence intervals is to find exact value of the true population mean based on random sample

Performing t procedure, its best to look at data first and then determine if you should do a one-sided or two-sided test

If a 95% and a 90% confidence interval were calculated,what would happen to the width of the 95% comparing to a 90%?

An approximate 99% confidence interval for an unknown proportion p is of the form ^p +- the margin of error.

The probability of an event is defined as the proportion of times an event occurs occasionally.