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Incremental reading


  1. Introduction
  2. Advantages of incremental reading
  3. Five basic skills of incremental reading
    1. importing articles
    2. reading articles
    3. converting articles to questions and answers
    4. repetitions
    5. handling knowledge overflow
  4. History of incremental reading
  5. Summary
  6. FAQ


Incremental reading is a learning technology that makes it possible to read thousands of articles at the same time without getting lost. It begins with importing articles from electronic sources, e.g. the Internet. The student then extracts the most important fragments of individual articles for further review. Extracted fragments are then converted into questions and answers. These in turn become subject to systematic repetition that maximizes the long-term recall of processed texts. The review process is handled by the proven repetition spacing algorithm known as the SuperMemo method.

Incremental reading may seem complex at first. However, once you master it, you will begin a learning process that will surpass your expectations as to what is possible in the area of knowledge acquisition!

Advantages of incremental reading:

  1. Massive learning: possibility of studying a huge number of subjects at the same time. In traditional reading, one book or academic subject might need to be completed before studying another. With incremental reading, there is virtually no limit on how many articles you can study at the same time. Only the availability of time and your memory capacity will keep massive learning in check
  2. Creativity: the association-creativity bonus. The essence of creativity is in association of remote ideas. By studying multiple subjects in stochastically unpredictable sequences, incremental reading dramatically affects association of ideas and immensely improves your creativity
  3. Understanding: the slot-in factor. One of the limiting factors in acquiring new knowledge is the barrier of understanding. All written materials, depending on the reader's knowledge, pose a degree of difficulty in accurately interpreting their contents. This is particularly visible in highly specialist scientific papers that use a sophisticated symbol-rich language. A symbol-rich language is a language that gains conciseness by the use of highly specialist vocabulary and notational conventions. For an average reader, symbol-rich language may exponentially raise the bar of lexical competence (i.e. knowledge of vocabulary required to gain understanding). Incremental reading makes it possible to delay the processing of those articles, paragraphs or sentences that require prior knowledge of concepts that are not known at the moment of reading. The processing will take place only then when the new information begins to slot in comfortably in the fabric of the reader's knowledge
  4. Entropy. The web is a goldmine of information. However, rarely do we find step-by-step articles that provide all information and entirely satisfy our needs. In scientific research, acquiring engineering knowledge, studying a narrow topic of interest, etc. we are constantly faced with a chaos of disparate and often contradictory statements. Incremental reading makes it possible to resolve contradictions and build harmonious models of knowledge on the basis of the information chaos drawn from the Internet. Incremental reading stochastically juxtaposes pieces of information coming from various sources and uses the associative qualities of human memory to emphasize and resolve contradiction
  5. Stresslessness. The information era tends to overwhelm us with the amount of information we feel compelled to process. Incremental reading does not require all-or-nothing choices on articles to read. All-or-nothing choices are stressful! Can I afford to skip this article? For months I haven't found time to read this article! etc. SuperMemo helps you prioritize and skip articles partially or transparently. Oftentimes reading 3% of an article may provide 50% of its reading value. Reading of other articles may be delayed transparently, i.e. not by stressful procrastination but by sheer competition with other pieces of information
  6. Attention. Incremental reading widely stretches the span of human attention. You will notice that a single paragraph in an article may greatly reduce your enthusiasm for reading. If you stumble against a few frustrating paragraphs, you may gradually develop a dislike of reading. Incremental reading makes it possible to immediately move on to other pieces of information. It also makes it possible to split larger pieces into less intimidating portions. Those measures dramatically increase your attention and the enjoyability of reading
  7. Consolidation. Incremental reading combines the process of extracting pieces of valuable knowledge with memory consolidation. By the time you begin a standard repetition process of well-formulated items, you memory will often have already been established in a close to the optimum context. This comes from the need to extract a given piece of information from a larger body of knowledge that provides your items with context, meaning, sense of applicability and representation molded by several approaches to the same piece from various context angles
  8. Prioritization: improved flow of knowledge as a result of more accurate prioritization of material. For example, reading lists in SuperMemo 99 required assigning Value to each article. Estimations of Value could be highly inaccurate. An interesting material that would receive a low Value might indefinitely wait in the queue for processing
  9. Fun. Maslov's hierarchy of needs and further research in psychology indicate that at a certain level of human development, the sense of productivity might be one of the most satisfying emotions. This is why incremental reading is highly enjoyable. This only magnifies its powers. However, to experience the elation of incremental reading, you may need a few months of focused practice. You will first have to start with the basic tools and techniques listed in this article. Then you will need to master knowledge representation skills. Finally, you will need a couple of months of heavy-load incremental reading to perfect the details and develop your own "incremental reading philosophy". Last but not least, incremental reading requires good touch-typing skills. Although the material is originally imported from electronic sources, it always needs to be molded, shortened, provided with context clues, restructured for wording and grammar, etc.
Only SuperMemo makes it possible to implement incremental reading. Incremental reading requires continual retention of knowledge. Depending on the volume of knowledge flow in the program, the interval between reading individual portions of the same article may extend from days to months. Repetition spacing is the foundation of incremental reading which is based on stable memory traces in-between reading bursts

See also: incremental reading from user's perspective by Len Budney 

Five basic skills of incremental reading

Incremental reading requires a collection of skills that you will perfect only with passing time and growing experience. This overview will help you handle the most basic skills and help you make a start with incremental reading.

  1. importing articles to SuperMemo
  2. reading articles and decomposing articles into manageable pieces
  3. converting most important pieces of knowledge to question-answer type material
  4. repetitions of the material (to ensure good recall of the learned knowledge)
  5. handling the unavoidable knowledge overflow

Skill 1: Importing articles

To import an important article to SuperMemo, follow these steps:

  1. Select the imported text in your web browser and copy the selection to the clipboard (e.g. with Ctrl+C)
  2. Switch to SuperMemo (e.g. with Alt+Tab)
  3. In SuperMemo, press Ctrl+Alt+N (this is equivalent to Edit : Add a new article on the main menu). SuperMemo will create a new element, apply the reading template (i.e. a template with one scaleable HTML component), and paste the article
  4. Optionally, use Ctrl+J to specify the first review interval (e.g. one day for high priority material or 30 days for low priority material)


Skill 2: Reading articles

You could precede reading articles with conveniently locating the Read toolbar on your screen. Choose Window : Toolbars : Read, place the toolbar in a convenient place on the screen and press Ctrl+Shift+F5 (to save the chosen layout as your default layout). If you do not see the Windows menu read about levels.

The Read toolbar:

This is a simplified algorithm for reading articles:

  1. Click the article (to make sure you enter the editing mode in which you can modify text, select fragments, etc.)
  2. Start reading the article from the top
  3. If you encounter an interesting fragment, select the fragment with the mouse and choose Reading : Remember extract (Alt+X) on the menu available with a right-click (or click the green T icon on the reading toolbar). This operation will introduce the extract into the learning process
  4. If you would like to adjust the first interval after which the extract review will take place, choose Reading : Schedule extract instead of Remember extract (checked T icon on the reading toolbar)
  5. If you read a fragment that does not seem important, select it and choose Reading : Ignore or click the stop-sign icon. The fragment will be marked with ignore font
  6. If the selected fragment does not include all the important reading context, you will need to add this context manually. For example, if you are learning history, you may extract the following fragment from an article about Lincoln: On Sept. 22, 1862, President Lincoln issued the Emancipation Proclamation, one of the most important messages in the history of the world. He signed it Jan. 1, 1863. If you would like to extract the fragment related to signing the Emancipation Proclamation, you will need to change He to Lincoln and it to Emancipation Proclamation so that your fragments retains all contextual clues: Lincoln signed the Emancipation Proclamation on Jan. 1, 1863. You can use the Reference options on the component menu to easily add proliferating context to your extracts
  7. Once you decide to stop reading the article before its end, mark the last processed fragment as the read-point (e.g. with Ctrl+F7). Next time you come back to this same article, SuperMemo will highlight your read-point and you will be able to resume reading from the point you last stopped reading the article. To go to your current read point, press F7
  8. If necessary, provide a meaningful title to your article. Occasionally, add some context clues at the place of the current read-point. Those actions may be needed to minimize time needed to resume reading the article without losing the context (context recovery overhead)
  9. After marking the read-point, choose Learn or Next repetition to proceed with review of other articles
  10. In incremental reading, interrupted reading is a rule, not an exception! (see advantages above)
    With a dose of practice, you will quickly get accustomed to this not-so-natural state of affairs and learn to appreciate the power of incremental approach. Use the following criteria to decide when to stop reading the article:
  11. Once you complete reading the article, press Ctrl+Shift+Enter (or Learning : Done on the element menu). This will dismiss the article, i.e. remove it from the review process. Done will also delete childless articles (i.e. articles that did not provide interesting extract or whose extracts have been processed and moved to target categories)
  12. If you have an impression the article is difficult and you would like to read some fragments later, extract those fragments with Reading : Schedule extract and provide a review interval that will reflect the time you believe you will be better equipped to understand the extracted fragment

Skill 3: Extracting fragments, questions and answers

In the course of traditional reading, we often mark important paragraphs with a marker. In SuperMemo, those paragraphs should be extracted as separate elements that will later be used to refresh your memory. Each extracted paragraph or section becomes a mini-article that will be subject to the same reading algorithm as discussed above. Extract your fragments and single sentences with Remember extract (Alt+X). Remember to add necessary context clues to make sure the extracted fragment does not become meaningless with time. If you cannot recall the necessary context, use the reference source link button on the element toolbar to jump to the article from which the extract had been produced.

SuperMemo will demonstrate to you that extracting important fragments and reviewing them at later time will have an excellent impact on your ability to benefit from the reading material at later times. However, it will also show that once the review intervals grow beyond 200-300 days, passive review will often become insufficient. At that time you will need to use Remember cloze (blue Z icon on the Read toolbar or Alt+Z). This option will convert single sentences into question-and-answer items.

For example, if you have extracted the following fragment from your reading about the history of the Internet:

The Internet was started in 1969 under a contract let by the Advanced Research Projects Agency (ARPA) which connected four major computers at universities in the southwestern US (UCLA, Stanford Research Institute, UCSB, and the University of Utah)

you may discover than when review intervals become long enough, you may not actually be able to recall the name of the ARPA agency or even forget the year in which the Internet started. You can then select an important keyword, e.g. 1969, and use Remember cloze to produce the following item:

Question: The Internet was started in [...] under a contract let by the Advanced Research Projects Agency (ARPA) which connected four major computers at universities in the southwestern US (UCLA, Stanford Research Institute, UCSB, and the University of Utah)
Answer: 1969

In the course of learning, you will yet need to polish the above item by manual editing it to a more compact and understandable form:

Question: The Internet was started in [...](year) under a contract let by the ARPA agency
Answer: 1969

The editing added the following benefits to the above item:

  1. purpose of the question: emphasizing the fact that the question is about the year in which the Internet began by using the (year) hint
  2. brevity: removing superfluous information. In the course of learning, you will answer the question and never focus on which universities were originally connected by the early Internet. If you believe this information is important, you will use the original extract to produce more cloze items that will focus solely on the universities in question. If you disagree, read: 20 rules of formulating knowledge 
  3. understandability: the ARPA agency may defy grammar rules you have learned at school but it is by far more understandable than just the ARPA. In SuperMemo contents and understandability are more important than stiff rules of grammar or spelling!

Important! Your work on extracting fragments, producing cloze deletions and editing them should also be incremental. In each review, do only as much work on the learning material as is necessary! Extracting and editing in intervals adds additional benefit to learning and is more time-efficient. Each time you rethink structure and formulation, you hone the representation and "connectivity" of a given piece of knowledge. In addition, your priorities change as you proceed with learning. At times it may result in over-investing your time in a piece of knowledge that is no longer relevant. The incremental approach should not only refer to the reading process but also to the follow-up processing and formulation

Skill 4: Repetitions and review

SuperMemo is based on repetition. You make repetitions of the learned material in order to ensure that your knowledge retention reaches the desired level (usu. 95-98%).

In SuperMemo, your incrementally processed articles will also be subject to repetitions. We will often use the more intuitive term review in reference to incrementally processed material; after all, when you resume reading an article after a certain interval of time, you are not actually repeating anything. You are simply delving into new sections of the same material and extracting newly acquired wisdom into separate elements (Remember extract).

The algorithms used to make (1) standard repetitions of question-and-answer material and (2) reviewing reading material are similar. Most importantly, all repetitions and review are made in increasing intervals. In incremental reading, you will constantly see inflow of new material to your collection. Unprocessed material will need to compete with the newly imported material. Increasing review intervals makes sure that your old material fades into lower priority if it is not processed quickly. Naturally, the speed of processing will depend on the availability of your time and the value of the material itself. Articles that are boring, badly written, less important for your work or growth, will receive smaller portions of your attention and may go into long review intervals before you even manage to pass a fraction of the text. That is an inevitable side effect of a voluminous flow of new information into your collection (and your brain). However, intervals and priorities can easily be adjusted. If the priorities change, you can modify the way you process important articles. Upon next review you can read the whole article or revert it to a short-interval review. You can even use search tools (Ctrl+F) to locate more articles on the subject you feel you have neglected and reprioritize these as well. 

The algorithm for repeating questions-and-answer (e.g. cloze deletions) is quite complex and you do not have much influence on the timing of repetitions (see: SuperMemo Algorithm). This stems from the need to keep a high level of knowledge retention, which can be compromised by manual intervention.

However, the algorithm for determining inter-review intervals in incremental reading is much simpler and is entirely under your control. Each article receives a number called A-Factor that determines how much intervals increase between subsequent reviews (the name A-Factor is used here for orthogonality; however, A-Factors here correspond to the extinct concept of E-Factor known from earlier versions of SuperMemo and should not be confused with A-Factors used by items). For example, if A-Factor=2, review intervals will increase twice after each review. A-Factors are determined heuristically on the basis of the length of the text and other factors. Long texts will receive low A-Factors (e.g. 1.1), while short extracts will receive higher A-Factors (e.g. 1.8). You can change the value of A-Factor associated with a given article by choosing Ctrl+Shift+P. A-Factors associated with items cannot be changed by the user.

You can also control the review timing by manually adjusting inter-review intervals. Use Ctrl+J (Reschedule) or Ctrl+Shift+R (Execute repetition) to determine the date of the next review. Ctrl+J will increment the current interval, while Ctrl+Shift+R will first execute a repetition and then set the new interval to the selected value. In other words, if you current interval is 100 and you specify the value of 3 in Reschedule, your new interval will be 103 and the last repetition date will not change. If you do the same with Execute repetition, you new interval will be 3 and the last repetition date will be set to today.

Skill 5: Handling large volumes of knowledge

With incremental reading, your work with SuperMemo will freely combine and mix reading with standard repetitions of knowledge. Randomizing the sequence of repetitions should be encouraged. Only random coverage of the material will provide you with a true sense of your progress. You can randomize your daily portion of repetitions and review with Learn : Random : Randomize repetitions (Ctrl+Shift+F11).

By using Randomize repetitions, your repetitions will not favor more accurate processing of material based on the length of the interval, element type (e.g. articles, extracts, question-and-answer items, etc.), contents (i.e. branch of the knowledge tree) or degree of processing. Random repetitions will help you better understand possible negative trends such as excessive inflow of new material, lower retention (mostly as a result of frequent rescheduling), poor formulation of newly created cloze deletions, low quality or applicability of the acquired knowledge, excessive emphasis on certain subject at the cost of other subjects, etc.

Your hunger for new knowledge may quickly result in substantial overflow of new material at the cost of the quality of knowledge and retention. For this reasons you may, but do not have to, decide to execute your repetitions in the following stages:

  1. random and indiscriminate review and repetition of all outstanding material
  2. random repetitions with the exclusion of topics (articles, and unprocessed extracts). With the help of Postpone you can postpone all topics or all topics except the most important articles as indicated by interval, AFactor, etc. Use Learn : Postpone : Topics for that purpose
  3. random repetition of all material with the exclusion of newly created and not fully processed questions-and-answers (mostly cloze deletions) (see how)
  4. random repetition of all question-and-answer material with selective delay of repetition in those branches of knowledge that can receive lower priority

Postpone makes it possible to reschedule only a subset of repetitions. For example you can opt to delay repetitions in these subsets:

Postpone uses a number called a delay factor that is used to increase intervals of outstanding repetitions. Intervals are simply multiplied by the postpone factor. For example, if you choose to Postpone with the delay factor of 1.1, all intervals will be multiplied by 1.1 and will increase by 10%. Postpone will always increase intervals by no less than one day from the present day. This way, all items on which Postpone is executed fall out of the outstanding subset. 

You will mainly execute Postpone with Ctrl+Alt+P in three ways:

  1. in the contents window: if you want to postpone a given branch of knowledge (e.g. new items)
  2. in the browser: if you want to postpone any subset of items that you can generate with browser operations (see: Using subsets)

  3. in the element window: if you want to postpone any ancestor branch to which the currently repeated element belongs

Here are some typical ways in which you will execute Postpone:

If you would like to make your repetitions using the above suggestions, you should add all your new material to a selected branch, and transfer individual items to target categories such as sociology, psychology, history, etc., only then when you are sure that these items have received their final wording and meet your stringent quality criteria. As a rule, you should not ever use Postpone on your mission critical knowledge. Postpone will reduce your knowledge retention. It should only be reserved for dislodging the excess of newly processed articles, extracts and cloze deletions. It can also be used sparingly on branches with lower priority (e.g. Private, Hobbies, etc.). 

To efficiently work with categories you should be familiar with the following subjects:

  1. using templates (providing different branches with different look)
  2. using categories (adding knowledge to different branches)
  3. flow of knowledge in SuperMemo (summary of skills related to the flow of knowledge between branches and knowledge pools such as memorized, dismissed, processed, pending, extracts, articles, etc.)

History of incremental reading

Incremental reading might be as important for SuperMemo as the original repetition spacing algorithm. It eliminates a number of bottlenecks to learning at the acquisition stage. 

Older SuperMemos: In the years 1987-1998, users of SuperMemo had only two alternatives in the area of collecting learning material for learning with SuperMemo: (1) type it in and formulate it manually or (2) obtain ready-made learning material from colleagues, SuperMemo Library, etc.. The only support for learning from electronically available material was via Copy and Paste.

SuperMemo 99 made the first step towards efficient reading of electronic articles by introducing reading lists and the first primitive reading tools: extracts and clozes. Reading lists are prioritized lists of articles to read. Extracts make it possible to split larger articles into smaller portions. Clozes makes it possible to convert short sentences into question-answer format by means of cloze deletions

SuperMemo 2000 greatly increased the efficiency of reading by introducing the concept of incremental reading. Incremental reading makes it possible to simultaneously read dozens of articles. Each article is read in small increments fully controlled and prioritized by the user and/or the default learning process. Components of incremental reading introduced in SuperMemo 2000: new A-Factor-based topic repetition scheme (i.e. learning algorithm), read points, formatting extracts and clozes (SuperMemo 99 would ignore formatting), text highlight and ignore, source article link, reading toolbar, branch and browser learning, branch and browser postpone, and support for longer articles (SuperMemo 99 imposed 64K limit on articles). 

SuperMemo 2002 brings incremental reading to a new level. For SuperMemo 2002, incremental reading becomes the primary learning mode for middle-level and advanced students. SuperMemo 2002 introduces HTML-based incremental reading. For the first time, the user will see little difference between the material in his web browser and in SuperMemo. Other new features introduced by SuperMemo 2002: wholesale learning material import from Internet Explorer, mid-interval repetitions that make it possible to review portions of material without damage to the learning process (Algorithm SM-11), search-based learning (i.e. subset learning in which the subset is defined by advanced search tools), dynamically modified A-Factors that fine-tune the priorities without user intervention, postpone wizard that obviates reading lists, separate topic/item statistics and new incremental reading progress statistics, reference labeling, and more.