By Deborah J. Confidence intervals estimate population parameters, such as the population mean, by using statistics for example, the sample mean plus or minus a margin of error.
To compute the margin of error for a confidence interval, you need a critical value the number of standard errors you add and subtract to get the margin of error you want. When the sample size is large at least 30or you know its standard deviationyou typically use critical values on the Z -distribution to build the margin of error. At roughly 25 or 30 degrees of freedom, the values of the t -distribution begin to match those of the Z -distribution.
So, a sample size of 30 is not an ironclad requirement, but it works well in many situations. To find a critical value, look up your confidence level in the bottom row of the table; this tells you which column of the t- table you need. Intersect this column with the row for your df degrees of freedom.
Across the top row of the t -table, you see right-tail probabilities for the t- distribution. But confidence intervals involve both left- and right-tail probabilities because you add and subtract the margin of error. So half of the probability left from the confidence interval goes into each tail. You need to take that into account.
Using the top row of the t -table, you would have to look for 0. The result you get using either method ends up being in the same column. Deborah J. About the Book Author Deborah J.He needed to be able to find a phrase within a specific field in a SQL Server database he was developing. If he received a "hit" then the process was to return the related value in a field within a parent table. He needed to only consider situations where the value of the field started with the phrase or if the phrase was the beginning of a word in the value of the search field it was a valid hit.
Read on and I'll explain further. Solution The web application being developed was for a medical website under which a user could select a phrase and search on various symptoms to return a related record in a table for possible malady. A phrase in this case could be multiple words or a single letter. Therefore if you selected your search phrase to be "B" and there were values in the search field of "Bone Mass", "Thumb Pain", or "Tumor, Benign" the results would be a positive hit on "Bone Mass" because the value starts with the letter B and "Tumor, Benign" because it is preceded by a space.
Even though the word "Thumb" includes the letter B in the search criteria it is omitted because it is, essentially, not the first letter of a word in the value. Let's dismiss the medical jargon for a second and take a look at an example where I relate the content back to SQL Server. For the sake of this example I will go on the basis that we have two tables: ProductChild with values pertaining to relational database management systems and ProductParent, which will be used to store just two records that state whether a given record in ProductChild is a SQL Server database system or not.
We will use "SQL" as our search criteria. There are two different approaches that can be taken to perform this query from this point forward. I will highlight both options and note now that the actual execution plan and execution times were identical.
We will ignore any results that do not meet this criteria, even if "SQL" appears in the field within a given word. These tables are extremely small. In the real-world scenario that prompted this article, we are also not dealing with more than a couple thousand records either.
Taking a closer look at this code it is extremely straight-forward compared to the ideas he and I tossed about: cursors, loops, all sorts of madness.
We end up breaking the two positive hit possibilities into two parts of an OR statement:. It accepts three parameters:. Ultimately this is probably the better solution as the format of the programming is consistent between criteria being searched upon.
There is also one less variable and therefore less overhead involved in this code block. Simply put, the code is more intuitive from a readability standpoint. Regardless of which option I use, the results are identical. ChildDescription and therefore receive these results for the query:. Of course the proper process is to encapsulate this into a stored procedure. Using what we just learned this is the final result:.
There are two approaches. In one approach create a Lookup Table, and then join the two.A probability distribution is a table or an equation that links each outcome of a statistical experiment with its probability of occurrence.
To understand probability distributions, it is important to understand variables. Generally, statisticians use a capital letter to represent a random variable and a lower-case letter, to represent one of its values. For example. An example will make clear the relationship between random variables and probability distributions.
Suppose you flip a coin two times. Now, let the variable X represent the number of Heads that result from this experiment. The variable X can take on the values 0, 1, or 2. In this example, X is a random variable; because its value is determined by the outcome of a statistical experiment. Consider the coin flip experiment described above.
The table below, which associates each outcome with its probability, is an example of a probability distribution. A cumulative probability refers to the probability that the value of a random variable falls within a specified range. Let us return to the coin flip experiment.
If we flip a coin two times, we might ask: What is the probability that the coin flips would result in one or fewer heads? The answer would be a cumulative probability. It would be the probability that the coin flip experiment results in zero heads plus the probability that the experiment results in one head. Like a probability distribution, a cumulative probability distribution can be represented by a table or an equation.
In the table below, the cumulative probability refers to the probability than the random variable X is less than or equal to x. The simplest probability distribution occurs when all of the values of a random variable occur with equal probability. This probability distribution is called the uniform distribution.
Uniform Distribution. Suppose the random variable X can assume k different values. Each possible outcome is a random variable Xand each outcome is equally likely to occur.In this table, the numbers 1 — 12 in the top row and first column are factors of the products listed on the inside of the table.
Since several of the products are listed more than once, the chart below can be very helpful. It shows every product in the multiplication table and the factors from the table that make those products. To save space both facts are simply listed as 5 x 3 with the greater factor listed first.
How to Solve a FIND THE FACTORS Puzzle
Only a few of the products are given as clues. To help you solve the puzzles, here are step by step instructions to solve a level 5 puzzle that includes most types of situations you may encounter trying to solve any of the puzzles. The object is to write each of the numbers 1 — 10 in both the top row the factor row and the first column the factor column so that those written numbers are the factors of the given clues.
There is only one solution. Here is a sample puzzle:. First look for the following perfect squares: 1, 25, 49, 64, 81, or because there is only one way to factor each of those numbers so that both factors are not greater than ten. In this puzzle, the 1 must be 1 x 1 and the 25 must be 5 x 5. Note that perfect squares 16 and 36 both have more than one way to factor them using only factors less than 10, so deal with those clues later.
Next look for a row or a column with at least 2 clues so that you can find a factor for both clues. This puzzle has one column and one row that qualify. Since 8 is the ONLY common factor meeting that condition, write 8 above that column and write 3 and 9 in the corresponding cells.
Since you have found the 3 in the factor column, try to find the 3 in the factor row. Write the 3, 7, 7, and 6 in the corresponding cells. Remember when we noticed that both 4 and 6 were factors of both 36 and 24? Therefore, you have found where the 4 should be written in the factor column. The only place in the factor column that the 2 can be written is in the cell next to the row with no clues. Write 2 in the factor row and 8 in the factor column. The only number 1 — 10 missing in the factor column is Now count from 1 to 10 while you determine what number is missing in the factor row.
In this case the missing number is Now all the factors have been found! It would benefit any child to see an adult filling in a table just for the fun of it. What a powerful example of lifelong learning would be set! My goal was to make the videos short, so each video is no more than 2 minutes 20 seconds long. Even though every row and every column of this puzzle has at least one clue, the logic is very complicated. Pingback: Find the Factors Mathematics - Games.
Okay, that was easier to understand that I thought it would be.Sometimes there is a need to find if a string value exists in any column in your table. Although there are system stored procedures that do a "for each database" or a "for each table", there is not a system stored procedure that does a "for each column". So trying to find a value in any column in your database requires you to build the query to look through each column you want to search using an OR operator between each column.
Is there any way this can be dynamically generated? Once again this is where T-SQL comes in handy along with the use of system tables or system views. The code below allows you to search for a value in all text data type columns such as char, nchar, ntext, nvarchar, text and varchar.
The stored procedure gets created in the master database so you can use it in any of your databases and it takes three parameters:. The first thing you need to do is create this stored procedure by copying the below code and executing it in a query window.
We recently ran into an issue that I worked on with Russ Mittler where the database setting had cursors set to local, so the script above did not work because it needed that setting to be global. This database setting can be checked using the below code:. So based on that issue, I wrote a different version of this stored procedure that does not use cursors.
That's all there is to it. Once this has been created you can use this against any table and any database on your server.
How Do You Calculate Input/output Tables?
Is there anyway to modify this so that for each record returned it can, in some way, indicate all the matches? Like list each column for each record to look in or highlight the matches in the results?
Yes I have tried for different tables, same issue.
If I am marking this as system stored procedure then the 2nd query working otherwise not. But while running it's giving all the users reside in that database. Tried in diffrent tables, databases.
Showing error like first query showing. Can I have a simple stored procedure not system stored to delete the user details stored in the databases specially string values. Yes I am putting the correct schema and object name, the second script you have written it's working for the same object and scema name.
But the thing is have to execute as system stored procedure. Can't it be simple stored procedure. Check to make sure object exists. Hi The 1st procedure works fine. But I need to know the column name where the string exists. Can I have that code.? With the following SP Modified from Option 2you can find the information in any Database on the current server by specifying the DB parameter:. I agree doing such tasks like these are necessary, but there are always downsides as you mentioned.
This is a good idea about dropping the unnecessary stats after the search.You may want to change the design of an Excel table or PivotTable, or refresh their data, or set some options for them.
You've read a help topic that mentions a command on the Table Tools or the PivotTable Toolsbut you don't see these tools. If you've selected an Excel table, you'll see the Table Tools with a Design tab. You can always ask an expert in the Excel Tech Communityget support in the Answers communityor suggest a new feature or improvement on Excel User Voice.
Format an Excel table. Rename an Excel table. Change the style of your PivotTable. Update refresh data in a PivotTable. Show or hide subtotals and totals in a PivotTable. Where are the Table Tools? Have the experts at Excelchat fix your formulas for free. See how. Need more help?
Expand your Office skills. Get instant Excel help. Was this information helpful? Yes No. Any other feedback? The more you tell us, the more we can help. How can we improve?Using the t Table to Find the P-value in One-Sample t Tests
Send No thanks. Thank you for your feedback! It sounds like it might be helpful to connect you to one of our Office support agents. Contact Support.Please ensure that your password is at least 8 characters and contains each of the following:. Enter a problem Hope that helps! You'll be able to enter math problems once our session is over. Algebra Examples Step-by-Step Examples. Check if the function rule is linear. To find if the table follows a function rule, check to see if the values follow the linear form.
Build a set of equations from the table such that. Calculate the values of and. Simplify each equation. Move to the left of. Solve for in the first equation. Rewrite the equation as. Subtract from both sides of the equation.
Replace all occurrences of with in each equation. Replace all occurrences of in with.
Remove parentheses. Solve for in the second equation.
Searching and finding a string value in all columns in a SQL Server table
Move all terms not containing to the right side of the equation. Divide each term by and simplify. Divide each term in by. Cancel the common factor of. Cancel the common factor. Divide by. Multiply by.
Sincethe equation will always be true.